BASIC FRESHWATER AQUARIUM PRINCIPLES; Information for the proper set up, maintenance, care and feeding for freshwater aquariums/ tanks By Carl Strohmeyer Updated 8/04/10 http://www.americanaquariumproducts.com/Basic_Aquarium_Principles.html AQUARIUM: Start with as large an aquarium as you can afford (even for bettas). The very BASIC principle that is to have 1-2 inches of NARROW bodied fish per FILTERED aquarium gallon is a starting point, but not very accurate. This also only applies to a standard rectangular aquarium. Goldfish are dirty and fatter, so I would triple this with them, in fact for long term goldfish health, one goldfish per 8-10 gallons is best (One goldfish per 30 liters). Obviously longer fish need more tank width and length. I would decrease the amount of fish proportional to the gallons in a tall aquarium or hexagon aquarium. Remember, many fish purchased can grow much larger than your original purchase size (ex: goldfish), so keep this in mind too. * To figure your tank size get your tank length, height, and width in inches then apply this formula (multiple all dimensions): L x H x W = X; Then divide X by 231 This gives you exact gallons of the tank. In round tanks or unusual shapes you will have to extrapolate. What is much more important in determining how many fish you should add to your aquarium are these factors: *The amount of surface area relative to the gallons of water the aquarium holds. I have observed many tall narrow aquariums over the years of my maintenance service where the filtration and other factors were equal to comparable sized and stocked rectangular aquariums, that general fish health and longevity were lower. *Type of fish, such as fish that naturally produce more waste (partly do to the type of food they eat) such as goldfish where one fish per 8+ gallons are better. Also a fish such as an Arowana that stays primarily on the surface will need a disproportionately large aquarium (I recommend 200 + gallons for just one Arowana). And as pointed out earlier, you cannot compare a heavy bodied cichlid for instance to a narrow bodied tetra of similar length. *Filtration, a properly filtered aquarium (good bio filtration, good mechanical filtration, and good circulation) with multiple filters is important. Good filtration with quality well maintained filters can go a long ways in allowing an otherwise small aquarium to hold more fish. *Maintenance schedule that includes regular efficient water changes *Well maintained water chemistry, including GH, KH and Redox not just low ammonia, nitrites, and nitrates. *New or experienced aquarist; a new aquarist needs to start with a much less crowded aquarium. *After proper feeding, good cleaning routines (20% water changes with a gravel vacuum once per week or two), proper feeding routines, good filtrations; If after all these are checked off and you still have nitrates that struggle to stay below 40-50 ppm, you probably have an over stocked aquarium (especially if there are live plants!). Also a kH and pH that starts out at proper levels, but then drops quickly after water changes and/or addition of stabilizing chemicals or products such as Wonder Shells can indicate over stocking (as well as other problems such as mulm buildup). Find a good Aquarium or Pet Store. Look at their fish and see how well they are taken care. If the store has central filtering system, be careful, as if one fish is sick in one aquarium it can be spread to all aquariums. Never buy fish from an aquarium with sick fish. In the aquarium stores I set up I never placed more than two aquariums on one system so if there was a disease outbreak it was easier to isolate. We also had UV Sterilizers on all systems. This is not to say that if you find a good dealer with a central system to not buy from them, just keep in mind if you see a tank of sick fish, the whole store may have been exposed. Many large retailers have central systems for their convenience, NOT YOURS. Finally as to tank size; this is often a controversial subject among aquarist, especially well intentioned advanced aquarists, HOWEVER one aspect is often missed and that is (as I explained above that gallons per fish is only a starting point) that although there is no denying that the bigger an aquarium you can afford, maintain or have space for the better for many good reasons, BUT I again have kept MANY aquariums under a variety of conditions and monitored them in controlled experiments and is often a small aquarium can work for what many might consider over crowded conditions provided excellent filtration, cleaning maintenance, circulation, feeding procedures (and quality food), chemistry, etc. For example you I can state categorically that 10 gallon aquarium with (2) 2 inch goldfish that is well maintained with a hang on the back (power) and a sponge filter will out have vastly better water parameters than a 20 gallon with the same goldfish that is poorly maintained with a corner bubbler filter. SUBSTRATE; For the average aquarium I recommend 2-3” of #3 or pea sized gravel. This tends allow for less build up of hydrogen sulfide producing anaerobic bacteria. The down side to larger gravel is that it will allow for more waste particle or eaten food to accumulate. With proper maintenance though, waste accumulation should not be a major problem. Sand is good for heavily planted aquariums, as it provides a better anchor for the roots and even more important sand traps nutrients and symbiotic bacteria needed by plant roots. If used for live plants, use ½” #00 or #1 sand followed by 2-1/2” of medium (#3) gravel, with substrates such as Azoo Plant Grower Bed or Eco Complete mixed in around plant roots. These two products can be substituted totally for gravel or sand (Although that can get pricy) FILTERS: I always recommend two filters minimum per aquarium for redundancy and for improved biological (denitrifying) filtration. For a small aquarium, a combination of a hang on the back (power) and a sponge filter. Or a sponge filter and an internal power filter. You want to make sure and rinse your sponge or cartridge out in used aquarium water to maintain your beneficial bacteria for bio filtration. Another note about the HOB filter is that they are far more efficient as bio filters if used with a sponge pre filter such a filter max. For larger aquariums a combination of a canister filter and an internal filter for cross circulation (I recommend Eheim, Via Aqua, Jebo- I do NOT recommend Fluvals as they have poor head pressure, high flow by rates and an un-reliable impeller). Other filters of note include the wet/dry, under gravel, and fluidized bed. There are four types of filtration: *Biological; the removal of nitrogenous waste (ammonia, etc.), which is the most important type. *Mechanical; the removal of larger debris (organic and inorganic) before it can go through the nitrogen cycle (organic) by means of filter fiber, sponges or other similar media. *Chemical; The removal of chemical contamination via carbon, zeolite or many other products. This becomes less important in a healthy, established aquarium. Carbon is often overused in healthy well established aquariums. If I even use carbon, I will generally use only one teaspoon per 5-10 gallons and then only change the carbon every 4-6 weeks. I do add more and change it more often in tanks treated with medication or a new aquarium. Carbon is often not necessary in established aquariums especially tanks with regular water changes and plants. I generally only use carbon to remove chemicals after treatment then remove the carbon. You can also leave old carbon to become a nitrifying bacterial colony. This point about carbon also lends credibility to Sponge Filters which are often considered poor filters due to the fact they provide no chemical filtration, this is based on poor information as to the need for carbon filtration. *Germicidal; The use of UVC or ozone to kill disease pathogens and control the Redox potential. HEATER: Most tropical fish do well at a temperature between 76 and 80 degrees Fahrenheit. (Discus prefer warmer). Goldfish do not need a heater. I recommend 25 watts for every 10 degrees of ambient temperature you need to raise your aquarium temperature. EX: If your home is 68 degrees and you have a 40 gallon aquarium, to reach a temperature of 78 degrees you would need a 100 watt heater. Also remember that bettas are still basically tropical fish too, so if they are kept in a bowl try and keep them in a warm area of your house, preferably above 70 F. A light does not pass for a heater, you cannot leave your light on 24/7 (an exception would be an Infrared reptile lamp, which are great for bettas). If your temperature fluctuates between night and day, even though you have the correct wattage heater, you may have an “Automatic” heater vs. a “Thermostatic” heater. Usually the cheaper clip on the back are automatic heaters; they respond to a setting (two contacts that are tightened for more heat), not by temperature. These heaters generally turn on and off at the same rate whether it is summer or winter (which is why they need seasonal adjustments). The best heater will have a separate temperature probe such as most Titanium heaters. Here are some examples of Thermostatic Heater (including Titanium): Aquarium Heaters WATER CONDITIONING: If tap water is used it will have to be treated to remove chlorine or even chloramines and heavy metals. Products such as “Start Right Water Conditioner” can remove chlorine and some metals and also break the ammonia/ chlorine bond in chloramines and remove the chlorine but leave the ammonia. “Prime”, Amquel Plus, Ammo Lock or similar products are good to use in municipalities where chloramines are used in tap water. Prime or Amquel Plus are excellent products to use when ammonia and nitrite levels are an issues, as these do not interfere with the cycling process as other products can. Salt is also commonly added to freshwater aquariums as a disease preventative, slime coat stimulant, or simply due to requirements by certain freshwater fish such as Livebearers or African Cichlids to have salt present the water. Generally 1 tablespoon per 5 gallons (35 liters) of water for a community tank is what works best. However this amount may be increased to double this for many livebearers such as mollies (please note that mollies need much more than salt such as calcium and other elements, I recommend reading this article for more information: “Mollies in Aquariums”). It should also be noted that some catfish (such as Cory Cats) are very sensitive to salt and care should be given in use of salt when these fish are present. Salts (and not just NaCl) do not evaporate and only small amounts are depleted by normal life processes of aquarium inhabitants, so slat should only be added back during water changes and ONLY for the amount of water removed (changed) to prevent accumulation. CYCLING (the Nitrogen Cycle): Your aquarium will not be at peak biological filtration for 6 weeks (or more). To start your biological filtration, there are many cycling products available, such “Cycle” by Hagen. My success with these products is mixed at best (in part due to the fact many are made with Heterotrophic Bacteria instead of the proper Autotrophic nitrifying bacteria); it is very difficult for the aerobic bacteria that are needed for cycling your aquarium to live in a sealed container kept at room temperature, as they die very quickly without oxygen and “food”. I prefer to add gravel and/or used filter sponge or cartridge from another aquarium. This method of adding media is much faster (you still have to take it slow), and provides all the necessary bacteria, the only negative is adding disease pathogens to your aquarium, but I have rarely encountered this problem. If you add plants (many such as hornwort remove nitrogenous waste), you can stock somewhat faster as the plants will remove ammonia too. We used this method for our Aquarium Maintenance route for years and never lost a fish to Ammonia or nitrite poisoning. Other methods method is fishless cycling include adding fish food to bring your ammonia to about 4-5 ppm or the use of un-scented ammonia where it is added into the aquarium (3-5 drops per gallon pure ammonia) so as to bring your ammonia level to 4-5 ppm. Then it takes about 2-6 weeks for the aquarium to cycle. The method of adding media is much faster (you still have to take it slow), and provides all the necessary bacteria, the only negative is adding disease pathogens to your aquarium, but I have rarely encountered this problem. Cycling is what is referred to as the Nitrogen cycle. Waste (nitrogenous) from the fish is broken down first from ammonia (NH3, the most toxic) to nitrites (NO2, less toxic) to nitrates (NO3, least toxic- but high amounts can stunt fish growth and lower disease resistance). At a pH of 6.5, NH3 (ammonia) converts to NH4 (ammonia) which is basically non-toxic to most fish (many ammonia removing chemicals to a similar ion change, as they do NOT actually remove ammonia). If you have plants in your aquarium they will directly consume the ammonia (especially hornwort), thus rendering the NO2 (nitrite) part of the nitrogen cycle null. The danger here is if your pH climbs above 6.5 the ammonia can change to much more toxic NH3 and the aerobic bacteria needed for nitrite consumption will be sparse. BASIC LIGHTING: For the average freshwater aquarium, lighting is not as important a consideration as it is for a planted freshwater aquarium or reef aquarium. However it still can make a difference on how natural your aquarium appears, as well as brown diatom algae is often a problem in established FW tanks with poor lighting (usually the incorrect spectrum, PAR %). There is also some evidence (not conclusive) that good lighting aids in correct Redox which is a water parameter that has an definite effect on fish health. The Eco light (pictured to the above left) is an excellent basic light fixture that clamps onto tanks that is simple yet utilizes more efficient newer technology (including high PAR). These light fixtures can be used in most any size aquarium however I generally recommend them for 20 gallon or less for single fixtures, although multiple fixtures work well for many larger aquariums. These same 6400 K high output CFL aquarium lights can also be purchased separately and used in standard incandescent aquarium (or other) light fixtures as pictured to the left. Another newer yet technology that is easy to adapt to basic freshwater set ups is the T2 Aquarium Light which is available in linkable fixtures for tanks from15 to 60 gallon (or larger depending on how many are lined). The T2 would be my recommendation for freshwater aquarium keepers that want a “step up” in lighting without a high price (the T2 out perform all aquarium lamps including older technology T5 in useful light energy output for energy used except for LED). Finally, good ole fashioned T8 & T12 aquarium lights such as the Aquarilux by Penn Plax that come in lengths from 12 to 48 inches are still practical for a basic FW aquarium application. Coralife, Hagen and Zoomed make comparable aquarium lights, all of which are excellent for colors of the fish, albeit lacking in lumens per output, PAR, and other lighting benefits (that are still helpful for a fish only aquarium). I would NOT recommend standard incandescent light bulbs (which are unfortunately still sold in many aquarium supply outlets) and STRONGLY recommend the use to the CFL aquarium lights referenced above to use in these fixtures. As well not all CFL you may see available in hardware stores, Walmart, etc are equal, the vast majority are of under 4500 K and not adequate for aquariums. Cool White lights also are not appropriate for aquariums due to poor lumens per watt, incorrect PAR and Kelvin output which can result in growth of Cyanobacteria or Brown Diatom Algae. Hardware Store/Walmart Grow-Light bulbs can be an inexpensive alternative and have a better PAR than most inexpensive bulbs, however even these have a low lumen per watt output and are not quite the bargain they may seem when this is considered. LIVE PLANTS: Live plants are desirable in my opinion, but many artificial plants can look quite realistic when properly arranged or used in conjunction with live plants. For a beginner live plants are more difficult, but not a lot. The benefits of live plants are they are great at nitrate removal and keep a natural balance to the aquarium, removing CO2 and adding oxygen (only during daylight). Hornwort is an excellent plant for nitrate removal (and even ammonia removal), and is relatively easy to grow. Banana plants (when available) are also a very easy plant. Be careful with many fish that will “mow down” your plants such as: Silver Dollars, most African cichlids, and even goldfish. For healthy plants I suggest a substrate of #00 sand mixed with Azoo Plant Grower Bed or Eco Complete about 3-5 cm deep with a layer of #3 gravel on top about 2 cm deep. This combination works well for plant roots, ease of vacuuming the top layer ONLY (where plant roots are), and for better bio filtration. You can substitute Azoo Plant Grower Bed with a sandy top soil (although usually not as good a source of iron), by preparing the soil thus; Gather sandy top soil, add water with a 10/1 bleach solution, mix for a couple of minutes, then rinse (with a de-chlorinator for first rinse) until the water runs relatively clear. The sand that is left is what you mix with your plant roots, please note that although an inexpensive route to go, this „homemade plant substrate is not as good as Azoo Plant Grower Bed or Eco-Complete. It is important to note that dying plants can add to your ammonia, nitrite, nitrate and even kH problems (production of nitric acid through decay), so is important to keep your plants healthy. For healthy plants you will need; *PROPER LIGHTING: 3-4 watts per gallon is a VERY basic principle, there is a lot more that goes into the equation than this. A couple is the light spectrum and temperature; Photosynthesis takes place at the blue end and even more so at the red end of the Nanometer curve (420 nm blue and 670 nm red). A bulb in the 5500- 6700 K range is generally best for plants. The Lux that reaches the plants is also important. *SUBSTRATE for a healthy root structure; This is provided by a good sandy base and careful cleaning so as to not disturb this. The roots are support symbiotic bacteria that aid in Nitrate assimilation and other processes. *BIO AVAILABLE CARBON and a Proper gas exchange: Good surface agitation where gasses such as Oxygen and CO2 are added/ subtracted from the aquarium. You can add to the bio available carbon and CO2 levels through a product called Sea Chem Flourish Excel , a CO2 generator, or by powdering some Ammo Carb (for carbon and Iron) into a fine powder and gently adding this with finger tips around the plants. The first two methods are more effective though. This is where there is a lot of misunderstanding, the key is bio available. This why I find the Flourish Excel a useful product as this is bio-available organic carbon. *PROPER NUTRIENTS OR ‘FERTS’: You will need a Nitrate level between 15-40 ppm, iron (best in the soil, which is where the laterite helps), LOW phosphate levels to help plants compete better with algae, and many other trace elements that should be present from fish waste with a proper feeding regimen. Some Plants to Have: • Hornwort (Ceratophyllum demerson) • Java Moss (Vesicularia dubyana) - • Dwarf Anubias (Anubias nana) • Java Fern (Microsorum pteropus) • Water Sprite (Ceratopteris thalictroides) FISH ACCLIMATION: Once you have removed your chlorine (if necessary) adjusted your temperature, checked basic water parameters (kH, pH, Ammonia), you can start with a few fish. It is best to wait at least 1-2 days for the first fish after initial set-up. Float the bag your new fish came in for 10 minutes, then open the bag and add a small amount of water. After 5 more minutes add some more water, and continue this process for about 30 minutes. After 30 minutes, gently remove your fish without adding ANY of the bag water to your aquarium to prevent disease transfer. FEEDING: I recommend feeding high quality fish and plant based foods. Quality ingredients include: spirulina, fish meal, FD Brine Shrimp, shrimp meal, Vitamin C & E, lobster shell. Fish cannot digest proteins from beef well, and fish get most their energy requirements from fats. Some quality foods include: Omega, Spirulina 20, Ocean Nutrition, Hikari, and Sanyu. For beginners feed you fish two to three times per day what they will consume in three minutes. This is a very basic rule and more applies to small fish and goldfish. This does not apply well to large fish, as I have seen Oscars and similar fish consume far more than they need in three minutes. Also large predators often only need to be fed once every day or two. I think the rule of feeding a fish based on their eye size better for large fish. Bettas in cool bowls will often only need a couple of pellets per day, Bettas in warmer (over 76 F) tanks or bowls or being prepped for breeding should be fed a varied diet twice per day Feeding foods high in poor quality proteins can increase your nitrate levels, as an essential ingredient in protein is nitrogen, and if unusable by the fish, it is excreted, entering into the nitrogen cycle. Just as importantly as to how much is how, I recommend with pellets in particular, but even with flakes to soak your food in water for 5 minutes prior to feeding. This softens the pellet, but more importantly prevents air from being released in the digestive tract and causing gas and infections. CLEANING: You should try and have a schedule of changing 20% (or more) of your water every week. I recommend using a gravel vacuum; you need not remove the fish while using a gravel vacuum. Make sure the water you add back in is the same temperature and ph, and has no chlorine or chloramines. For established aquariums you can go longer between changes, especially well planted aquariums. Use the Nitrate levels as a gauge, if your Nitrates exceed 30-40 ppm (depended on your fish tolerances), change water. CHEMISTRY (& TEST KITS): Keep your ammonia level at 0, your nitrite at 0, your nitrates below 30-40 ppm (not less than 15 ppm for planted aquariums), and your KH above 80 ppm. Ph depends very much on the fish you are keeping. Discus prefer under a ph below 7.0, while Mbuna African cichlids prefer above 8.0 A very general ph of 7.0 -7.5 works for many community fish. Crushed Coral (aragonite) and Sea Chem Buffer can help maintain a high pH when you desire an aquarium with a higher pH, KH, & GH, especially where tap or well water is very acidic. Wonder Shells along with crushed coral can help with important mineral cations (although crushed coral does not dissolve at a rapid enough rate to help as well) For a lower pH in aquariums where the tap water used is very high (usually 7.8 or above), I have used blends of RO (Reverse Osmosis) water and tap water. The ratio varies with the tap water pH, KH, & GH and the water conditions I want to achieve. With Discus it can be as high as 75% RO. Then to maintain these conditions I use peat in my filters. Another newer method for lowering pH is crushed almond husk found in Nirox Bio-Lif (instead of, or in addition to peat, to which it is superior do to this products bacterial absorption properties and superior pH lower capacity), this actually works quite well. Note that GH does not directly affect pH, calcium and magnesium (major ingredients of GH) is important to fish metabolism. Also note that calcium is also important for fish metabolism and fish health and healing. With the above method of using RO (or DI) water in a blend with tap water and peat, I have still been able to maintain a KH of 80 ppm (for proper calcium absorption), sometimes with additives such Wonder Shells or Calcium Polygluconate. Maintain: *Ammonia/nitrites; 0 *Nitrates; under 40-50 ppm (lower yet is always better) *GH: this is best above 100 ppm for 99% of FW fish and above 200 for over 60% *KH; VERY important for pH stability which is why I this is a more important test than pH in my experience and knowledge of aquarium chemistry. *pH; stable is most important, but for general community tanks a 6.8-7.8 falls within most fish tolerances as long as there is pH stability since the pH scale is logarithmic. Please know the fish you keep for what is best, but again I want emphasize stability over actual number. Please see this article for more on this subject: “Aquarium pH, GH, KH” Test Kits; It is always best to have as many different test kits (that apply to a freshwater aquarium) as you can afford. I will list them here along with a generalized recommendation of what the water parameters they test should be: *Ammonia Test Kit ; Very toxic even at low levels, should be kept at or near 0 Please see this article for more about lowering ammonia and preventing high aquarium ammonia: Aquarium Nitrogen Cycle and Cycling *KH & GH Test Kit ; A KH of 50-150 and a GH of 100-250 is generally best (depending upon fish kept). I actually recommend this test kit(s) over a pH test Kit, this is due to the fact that a poor kH will make keeping a stable pH nearly impossible. Also Calcium (as tested in GH) is more important to fish health than many aquarists give credit (see my article: CALCIUM, KH, AND MAGNESIUM IN AQUARIUMS; How to maintain a Proper KH, why calcium and electrolytes are important) *pH High Range OR Low Range Test Kit ; Stability is what is most important as to pH, as an unstable pH (sometimes caused by using pH up or down products) is vastly more dangerous than the actual number (depending upon the fish kept). Again see the above recommended article for more about pH as well as KH/GH. *Nitrate Test Kit ; Under 50 ppm is best, although many fish can tolerate up to 100 ppm for short durations with no problems. This test is also important to know when to change your water (along with KH), as well as how well your general long term tank health is going. For more about Nitrates, please read this article: Aquarium Answers; Nitrates *Nitrite Test Kit; As with ammonia, at or near 0. This parameter mirrors ammonia often within hours or days. I prefer to purchase my test kits separately as most master test kits duplicate test I do not need (high range and low range ph) and leave out ones I need such as kH and GH. *Test Strips, although generally not as accurate are still very useful for quick readings that are still accurate enough (provided stored dry) for an aquarist to get a good barometer of aquatic health. The API 5 in 1 Test Strips provide 5 key aquarium parameters including the often missed KH and GH test. SMELLY WATER: Generally there are three basic “Smell Problems”  Rotten Egg; This is Hydrogen Sulfide. Make sure you do not have anaerobic activity under rocks or other areas oxygen cannot reach, this can also happen in fine sand (without plants) more than 1-2” thick, I recommend #3 gravel or pea sized gravel when there are no plants. Also canister filters that are turned of for more than a few hours, and then switched back on can produce this.  Ammonia smell. This basically means your aquarium in not Cycled properly or you have poor filtration, over feeding. Either way you have high ammonia. Prime can help de-toxify the ammonia, then change water, add filtration if needed, and follow other procedures outlined in our article : Aquarium Nitrogen Cycle and Cycling .  Just a dirty aquarium smell; This simply may be over aeration at the surface of the aquarium allowing the “aquarium smell” to be expelled into the room. Proper cleaning or Redox also may be a problem. If water parameters are good, a Wonder Shell may help for this GREEN WATER: Green water is free floating algae. The main causes are: *High waste particulate matter in the water column (DOC), which over crowding, over feeding and also important here is improper feeding (poor quality food that is mostly passed thru the fish, usually non aquatic amino acids an too much cereal are the culprits here) *Intense or incorrect lighting; the use of household standard light bulbs or cool white Fluorescents can contribute to poor lighting that encourages “pea soup” water. Also placement of the aquarium at or near a window can also be a major contributing factor to this problem. *Poor water parameters; Nitrates and phosphates to high, GH or kH to low (best above 100 and 50 ppm respectively), Redox should be -300 mV (don't rush out and buy a test kit for Redox, there are simple ways to check it). This usually goes with the high waste particulate problem and can affect kH and more importantly Aquarium Redox (which measures the water oxidation and reduction potential. Corrective measures: *20% water change (or more) using a Gravel Vacuum (especially to remove nitrogenous waste producing mulm than often accumulates under rocks or UGF plates) *Add a UV Sterilizer. Usually 100% effective when a quality unit is properly installed but not always cost effective for small aquariums (although the Terminator UV Sterilizers are compact, of high quality design and cost efficient), but are worth mentioning, not just for sterilization, but for Redox which plays a role in algae control including bacterial BG algae. A UV Sterilizer is almost 100% effective in the eradication of green (pea soup) water, so if you can afford this option, I would use one. Please click on the picture above/left for a larger view of a before and after picture using a UV Sterilizer to clear green or cloudy water (Photo courtesy; Paul Phillips) *Reduce your fish numbers *Electrolytes and minor elements such as magnesium and calcium Wonder Shells are useful here so is aragonite in the filter) *Cut back on feeding and improve food quality (No TetraMin). Better choices: Ocean Nutrition, HBH, Spirulina 20 just to name a few. For more about proper feeding, please read this article: Quality Fish Food; What ingredients are needed for proper fish nutrition, growth and health. *Increase circulation and dissolved oxygen. *Make sure your Nitrates are below 40 ppm, your GH is at least 100 ppm and KH at least 50 (depending on fish kept), your phosphates as close to 0 as possible. *Move your tank to a different location if near a window or other bright lights (being next to a window is often major contributing factor), or improve lighting to 6400 K lights if low quality lights are an issue such as the T2 Aquarium Lights or the Compact Fluorescent Aquarium Lights, both come in 6400 K. Please note that even good aquatic lights loose much of their lumen output outside of the visible light spectrum within 6 months, & even more so after a year, so if your aquarium light is not the best light spectrum (6000-8000K) or is more than a year old changing it is a good idea. *Add poly filter pads to your filter (these can be cut an placed in front of a filter cartridge in such HOB filters such as a Whisper or VitaLife, as well as the foam blocks of Aqua Clears). See this article for more about ploy filter pads and other filter media: Aquarium Answers; Aquatic Filter Media *Magnets can be added to your filter or water lines (place away from the impeller in HOB or similar filter). This is actually more effective than many may think, although this method is best used in conjunction with other methods noted here. Magnets work by removing iron from the water that free floating algae need for photosynthesis. I do NOT recommend using magnets in tanks with live plants, although green water is often less of a problem in these tanks. *Add aquatic plants to compete with the free floating algae for nutrients, light (please see the article about plants a couple paragraphs below) *Add copper or products such as Medicated Wonder Shells that contain Copper and Methylene Blue that kill free floating algae, however even if this corrects the problem, this more addresses the symptoms than the cause from my experience *Finally if water changes are not removing enough organic debris from your substrate (this is a last ditch effort IMO), consider washing 50% of your gravel (or even 100% if you have healthy establish gravel that can be moved from another aquarium to this one after finishing). WHITE OR GREY WATER CLOUD: A white or grey cloud is a bacterial bloom. The main causes are: * A poorly cycled aquarium (usually new aquariums) * Overfeeding * Poor Filtration * Over crowding * Poor water parameters (including GH) *Too high a bio load (which can have many causes such as poor filtration, poor cleaning procedures, too many fish, overfeeding and is basically a summary of some of the above problems) *Over population of Detritus Worms (also identified white worms or misidentified as Planaria) resulting from decaying matter, low oxygen content. Corrective measures: *Change 20% of your water every other day until improved *Cut back on feeding and improve the quality of food and feeding method, refer to my article Quality Fish Food; What ingredients are needed for proper fish nutrition, growth and health. *Add additional filters or improve your filters such as by adding a Filter Max Pre Filter to your HOB or Canister filter. Also follow proper aquarium filter cleaning procedures by only changing part of your media and rinsing the rest in non chlorinated water. *Remove Fish *Add a UV Sterilizer (100% effective but not always cost effective for small aquariums, but is worth mentioning, not just for sterilization, but for Redox Potential) *Make sure your ammonia and nitrites are 0, your GH is at least 100 ppm (depending on fish kept) and your Nitrates are below 40 ppm. In established aquariums GH which is the source of electrolytes and Redox, can drop and occasionally be a source of cloudy water from my experience. *If the “cloud” is the result of a temporary cloud caused by overcrowding, or especially decomposition from rotting fish food, excess waste, or dead fish or other aquatic inhabitants that were not removed in a timely manner, the use of Potassium Permanganate found in products such as Jungle Clear Water may quickly solve this problem, however this often may be a temporary fix if other problems exist. Please also read this article about the use and cautions of Potassium Permanganate use: Aquarium Medications 3; Potassium Permanganate *Sometimes particulates can be a problem in established aquariums, especially after cleanings and the use of products such as Crystal Clear may help (I do not recommend this in new aquariums under two weeks old). Aquarium Cleaning Machines or Diatom filter may help with cloudy water problems in established aquariums, especially if this occurs after water changes and if this is the case, I highly recommend the Aquarium Cleaning Machine.