Frequently Asked Questions
Every fish-keeper comes across problems with their tank or fish at one time or another. I've listed a few common tank problems, but if you don't find what you're looking for, you can email me and I'll get back to you with more information. Have a look through my pages for further information on chemical imbalances and tank problems.
Q: Why is the water in my tank green and cloudy?
A: This can be due to a number of factors. Excess algae is a sign of poor water quality. This extra growth can result from uneaten food, high phosphates and high nitrates. Regular water changes of about 10 or 20% will reduce any chemical imbalances in your tank. Test the phosphate levels in the new water, to make sure you're not adding more unwanted chemicals. Water changes are the best way to deal with this problem, just be sure to make small water changes to reduce the stress on your fish. I refer you to my Tank Chemistry page for more information on regulating the chemical balance of your tank.
Q: Why is the water in my tank cloudy and milky white?
A: The bacteria population multiplies rapidly during the early stages of setting up a tank, to use up all the available nutrients. It's been shown that there may be 100 million bacteria per gram of filter sand after two weeks of cycling a tank! It is important to let your tank and filtration settle in before you add your fish. This allows the biological process to develop and ensures the cleanest water for your fish in their new home. Thoroughly clean all your equipment and rinse substrate before you add it to the tank, to reduce waste from the outset. Bacteria grows quicker in warmer conditions, so dropping the temperature by a degree (Celsius), may help to reduce the cloudiness.
Q: My fish are all taking air at the surface. Why?
A:This is a sign that there is not enough oxygen in the water. If your fish continue to gulp air they may become bloated, so it is important to rectify the problem quickly. Check any air pumps or filtration systems you may have, make sure they are clean and unblocked. A small water change will help to oxygenate the water. Check your fish for signs of stress - flattened fins, listlessness, bloatedness - and make sure they're ok. As always, any changes you make need to be small but you can do water changes every two or three days, as required. Adding plants to your aquarium will provide extra oxygen for your fish, and a place for them to shelter and breed.
Q: My fish has white spots all over its body and is scratching. What's wrong with it?
A: This is a sign of saltwater ich in marine fish, or white spot in freshwater fish. You can diagnose this condition by checking for little white spots on the fish's body - it may look as if it has been sprinkled with salt. Ich is a parasite that burrows beneath the outer skin, and chemical control is the best method of treatment. You can add most of these treatments directly to the tank, but read the instructions carefully. Some freshwater species are sensitive to this and require a lower dosage, ie. clown loaches and naked catfishes. In marine aquariums, you can use a copper treatment, but you must remove the fish and treat it separately if you have marine invertebrates, as they cannot tolerate copper. There are also many products available for boosting your fish's immune system, such as garlic or nutrient sprays. This will help to prevent further infection.
Q: One of my fish won't eat. What can I do?
A: Your fish may stop eating because of illness or even sometimes loneliness. It may also be a sign of poor water quality. Check the chemical levels in your tank to make sure the nitrate and ammonia levels are safe. Clean and oxygenated water will help revive stressed or unhappy fish. Make sure your fish's mouth is free of parasites or infections, or anything that may physically be preventing the fish from eating. Try hand-feeding your fish with a nutrient rich food. Be aware of the size of the fish's mouth - is the food you're giving your fish suitable for them to eat? Is the temperature correct? Higher temperatures reduce the oxygen levels in the water and can make fish listless. Some species just like to be with their own kind. Clown loaches, for example, can fade away if they are kept alone. Even a community tank may not be enough company for them.
Q: How can I clean the glass on my tank?
A: There are many great products available now, two of which I use frequently and would highly recommend. Magnet cleaners are great - one half is inside the tank and one half outside. All you have to do is rub it across the glass and it removes any algae or residue leaving your glass clean. Another recommendation would be for a Tetra product, which is essentially a squeegee blade on a long handle, which you can use to clean the inside of the glass. This is much better for cleaning stubborn algae or lichen. This second method can be less disruptive for the fish, as the magnet method will disturb the water a little.
Q: What kind of filtration do I need in order to keep corals?
A: The best filtration for keeping corals would be the protein skimmer. You can run one instead of the internal filtration. Protein skimmers remove all the waste from the water continuously. Some people dislike them because protein skimmers cannot distinguish between the waste and good bacteria in the water. However, due to the sensitive nature of corals, I would recommend a protein skimmer. I use one myself, and my nitrates have been easier to control since I installed it. However, speak with your local fish shop - some hardier corals can survive without the use of a skimmer provided the water quality is good.
Q: My clownfish keeps biting me. What can I do?
A: This problem is more common than you may think, and it's one I personally experience on a weekly basis! If your clownfish (or other species) is nipping you, it may be because you are in their territory, or because the fish is preparing to breed. Alternatively, some fish just like the taste of certain people! Occasionally, if my clownfish bites a little too much, I require another set of hands to keep the fish away while I complete my task. Although the bites can sting for a few seconds, the fish will not do you any harm, and unfortunately there is little you can do!
Q: There seem to be a lot of tiny bubbles in my tank. Is this bad?
A: Micro bubbles occur quite commonly, and it may be for one of several reasons. Is your pump adjustable? Reducing the flow will help to reduce bubbles. If you have a skimmer or top-up system, try to set it up so that the new water is added under the surface of the tank, and is not falling from a height. This will drastically reduce the occurrence of micro-bubbles. It is not ideal to have micro bubbles, as they can cause problems with fish mobility. Also the fish process the oxygen in the water, and it is just as bad for them to have too much oxygen as it is too little. Don't panic, but do see if you can make any adjustments to reduce the bubbles. Sometimes the tank may settle down on its own after a few minutes.
Q: The water in my tank seems really yellow but I don't know
why.
A: Do you have any driftwood in your tank? Driftwood often leeches brown or yellow colouring into an aquarium. It's completely harmless, but if you're unhappy with your tank you can try sandblasted driftwood, which will not leech. Do you have anything in your tank that is not intended for aquarium use? You must only ever add specialist aquarium products to your tank, as many glues and plastics are harmful to fish. Foreign objects can often be the cause of poor water quality and sick fish. Again, small, regular water changes of about 20% maximum will do the trick, alongside removing anything which is unsuitable. A good gravel clean will also remove any unwanted or degrading matter.
Q: What is the right amount to feed my fish?
A: Your fish should be able to eat what you give them within a few minutes. You can feed your fish as many as four times a day, but the more often you feed, the less food you give them. I personally feed my fish morning and evening. Flake food is great because it floats for a while, making it easier to remove any unwanted food. Place the flake on the surface so the fish can eat it as it falls and it won't fall to the bottom and be left uneaten. Overfeeding is often a major factor in poor water quality, as it increases ammonia, nitrites, nitrates and phosphorous. See Tank Chemistry.
Q: How can I feed my fish if I'm on holiday?
A: Nowadays you get get lots of different fish feeders, which will feed several times a day for up to two weeks. Check your local fish store or one of my recommended sites and you'll see the range on offer. Prices vary greatly so shop around for the one that suits you and your tank best.
Q: How can I regulate the temperature in my tank in the summer, and stop it from rising?
A: There are a couple of ways of doing this. Firstly you can buy a cooling device which, similar to a thermostat, maintains the temperature you set. Alternatively, on a very hot day if your tank is heating up, you can float bottles of ice on the surface of the tank. This will settle the temperature slowly without disrupting your fish. Also, if the ambient temperature in the room is several degrees hotter than usual, you may want to adjust your heater thermostat to a lower level to counterbalance it.
Q: My skimmer isn't creating any bubbles. Why isn't it working?
A: The most common cause of a protein skimmer failing to work properly is a salt blockage. Often the tiny air pipe which connects to the skimmer can become blocked with salt. Without any air the skimmer will not function properly. Turn off the skimmer, unplug the main pump section, remove the air tube and thoroughly clean it, then replace it. Remember that a skimmer removes waste, so if your tank is very clean the skimmer may appear to do nothing. It is advisable to clean your skimmer (at least the main pump section) about once every couple of months to make sure salt deposits don't build up.
Q: One of my fish is getting bullied by the others and I'm worried it will be killed. Is there anything I can do?
A: Unfortunately this is nature taking it's course, and natural selection. Sometimes a small or injured fish may become a target. My advice is to watch carefully to see how severe the bullying is.If it's severe and you don't want to see the fish die, you can try quarantine or putting the fish in a fry net for protection. Once the fish regains its strength then you can try putting it back into the main tank. However, we are talking about natural selection, and often it's best to let the fish fend for itself. If it's getting bullied in your tank, there's no guarantee the same won't happen if it's moved into another tank. This happened recently to one of my own green chromis. After a hairy few days and being outcasted from the group, the runt is slowly gaining confidence, and I think he will settle in again. Be sure to watch and make sure the fish is getting enough to eat - often bullying amounts to preventing the victim from getting any food.
