let me guess looks like white spider web right?
I think that's
Cloudy Water
* water is cloudy or hazy
* white mold-like growths on rocks, plants
* "googey" pieces of debris cling to gravel
* fish become listless, increased chance of fin rot Cause: This is the most common problem experienced by beginners. It is usually due to:
1. Overfeeding: We have found that over 80% of cases of cloudy water are due to overfeeding. Decaying food creates a bacterial bloom and clouds the water.
2. New Tank: Cloudy water often occurs for a few days after you first set-up a tank. Maintain normal filtration and the tank will clear on its own. "Brite and Clear" , or "Filter Aid" tonic will speed the clearing.
Treatment: Do a partial water change of 25%. Review feeding procedures.. Maintain adequate filtration, and use fresh activated carbon in the filter. Add "Brite and Clear" tonic.