As it was explained to me, the cloudiness is from lots of ammonia-eating bacteria floating free in your water. (The bacteria are good.) My tank is also cylcing, and I've been doing 20-30% water changes every one or two days, depending on how bad the water quality gets (as I was advised.) It keeps the water clear and healthy for the fish.

However, I'm pretty new to the whole aquarium thing (just graduated from carnival gold fish), so maybe there's another cause. But I thought I'd throw that out there so manybe you can try it while waiting for someone who knows more to respond. :) It certainly couldn't hurt.

"New Tank Syndrome" that´s what you have, the cloudiness you are watching is caused by a bloom in the nitrifying bacteria and until the population of nitrifying bacteria increases to the point where it can deal with the ammount of ammonia the biomass is producing the cloudiness won´t go away, once the nitrifying bacteria population is enough it will attach to the surfaces and the cloudiness will dissapear. NEVER add PH down to a populated tank, you can kill the fish. Do not add AMMO-LOCK, in that stage the product is good for nothing, it´s like putting on a band aid on an eviscerated patient, what you need is a long term product that will continously remove the ammonia while the nitrifying bacteria population can begin to deal with the ammount of ammonia, use zeolite in your power filter instead.

Is this an new tank or an established tank that suddenly became cloudy ?

If it is a new tank the most common reason for new tank syndromes is overstocking the tank in a short period of time.

If it is an established tank then it´s telling that:

1.- You have been adding nitrogenous compounds to the tank ( overfeeding )
2.- That the biomass has exceeded the filtering capacity of the biological filter ( fish too large )
3.- That something has died and you haven´t noticed it ( dead fish, rotting plants )
4.- That the filtering media is completely clogged with debris.
5.- That the bacteria has died and there´s nobody to deal with the waste.

Check and correct any of the above and the problem will solve on it´s own in a couple of days.

Billy wrote "Hello; I have a 29 gal. with 4 gouramies; 2 sharks; 2 dinas(?)(long silver/gold stripped fish)1 snail and 1 pleco; 3 live plants and various plastic plants; 3 large rocks on a bed of gravel. All fish are appox 1 1/2-2 inches long. I started the tank about 2 weeks ago" ---You have too many fish to start a tank. The sharks and pleco (unless the pleco is a dwarf variety) will out grow a 29 Gallon tank, Plecos can get 18"+, Sharks the same or bigger. Most sharks are semi-aggressive and not really suitable for a peaceful community setup. They get more aggressive as they mature. The cloudiness is normal for this time as everyone else said just a bacteria bloom. Your ammonia level is most likely very high and very toxic now. When the bacteria establishes the ammonia level will drop to 0 and nitrites will start to show. They are toxic and can be blocked with salt. Read the link below for better detailed info. As far as the products you are using Cycle, pH down and ammo lock. Just stop using them. Cycle can end up killing the bacteria it is supposed to help, usually does and prolongs the establishment of the cycle. pH down is only a temporary fix. Once the acid thats in it burns up your pH climbs right back up. Ammo lock is a dechlorinator as well as an ammonia blocker. Since you have to use a dechlorinator for your tap water only use one at a time. Some of them similar to ammo lock also remove chlorine, chloramine and detoxify ammonia and nitrite, can be double dosed or more for the purpose of the extra ammonia. Don't try this unless the label says its OK. When you have used up the dechlorinators you already have buy "Prime" it treats more water using less because its highly concentrated. The other ones have larger bottles with more volume for the same as a smaller bottle of prime but they don't treat as much water. A bottle of prime treats 3 times the ammount of other brands. It also can safely be used 5 times the suggested dose to block ammonia and nitrite. Your money would be better spent on a master test kit like the laborett or API. This way you can monitor water parameters through the cycle. Other ways to reduce and/or block ammonia is 1) water changes to dilute the concentration. 2) feed less food every other day or once every 3 days, dont worry the fish wont starve. less food= less fish poop and less uneaten food = less ammonia 3)lower temperature and try to keep pH down if possible with PWCs. lower water temperatures and pH make ammonia less toxic.

Here is a link that might be useful: beginner FAQs, the nitrogen cycle