So, I've had my wonderful betta fish for about a year now and there's just one pesky problem that won't go away. It started when I moved him to a bigger tank (he's in a 5-6 gallon tank now). The tank has a filter and the water stays perfectly crystal clear and all of it's readings for ph and everything (i have it tested monthly at Petsmart) are normal. So, being that he seems healthy, eats like a horse, the tank doesn't get dirty and all of it's things are normal I wouldn't think I'd have this problem.
About the time I switched him to the bigger tank the top of the water started getting this oily coat, like when oil and water mix. Well, that only lasted for about a week and then it started to kind of gel over. Not really gel, just this thick layer right on top (which doesn't stop him from coming up for air) that turns into this papery little bits when I touch it.
If I fully clean the tank it comes back in about a week. Partial changes about 3-4 days and just skimming the top with a special net i keep just for the purpose about 1-2 days. Does anyone know what it is/what causes it and how I can get rid of it? As you can see in this >>>> http://s63.photobucket.com/albums/h1...t=IMAG0039.jpg
<<<<< picture the water stays perfectly clear and only the top is affected. (And no, there are no live plants in the tank!)