Hi,
We set up a new 55 gallon freshwater tank about 4 weeks ago. After 2 weeks it got really cloudy, so we started doing 10% water changes 2 or 3 times per week. After 1 week it started clearing up, and then all of the sudden it's REALLY REALLY cloudy again! And the fish are looking sick. Any advice?

How many fish did you put in the tank. You have a Urine surge. put an amonia pillow in the filter and let the tank cycle completely and do not add any more fish. You must ad fish gradually or this will happen. Change water l/3 every l0 to l5 days. You are not allowing the natural bacteria to help clear the tank out. What type of filter system you using, back, under counter, under gravel? or combination. Also picking up a diatom filter will also clear this out . Whatever you do, do not add or get any more fish till it clears. As it will only compound the problem.

Is it a green cloudy or a white cloudy?
If the cloudiness is green it's algae. The only way to really get rid of it is to put a blanket over your tank for a couple weeks so no sunlight gets in. If it's a yellowish or whitish cloudy, it's the food. Change the quality of food you're giving the fish.

Sounds like a possible ammonia spike to me. You probably added too many fish, too soon. You also need to use a carbon filter, even if for a short time. Take it slowly, that is the #1 mistake in setting up a new tank. Bad things happen fast if you don't know what your doing.

You have what is called "new tank syndrome". It is basically an ammonia surge. I would do a 10% water change every 3 days, but lightly suck the substrate unless you see unused food or feces.

I presume you are using an UGF? The ammonia removing catridges work well in the uplift tubes during this process.

I would do 3-4 water changes and then test it!!

Peizn

Peizdobes is rite

I had the same problem with my tank what i had to do was clean my rocks out really good my filter and snails where not doing there job I have not had a problem with it clouding up yet