The Puffer Forum

I missed that lol.

RTR wrote:I don't think it is Cyanobateria - (among the "best" biofilm builders around, and that is too splotchy).

What size is the fish now? You may be overdue for a tank upgrade. In any case, it is nutrients plus too much light. If you want that many hours per day, you need to seriously downgrade the lighting - reduce one o\r the other (time or wattage) by at least 50%.

Reaperpilot2014: The tank is SW not fresh. FW snails will not survive, even if they were not eaten.

Lights and phosphates are a good guess... But before we decide anything, I'm with RTR... what's the whole situation here?

Water change schedule?
Size of fish?
Age of tank?

Just because you don't have any amonia and minimal nitrates, doesn't mean that there aren't dissolved minerals (lack of a better word) in the water. There could be something that we can't test as hobbyists (RTR doesn't count here ).

Once you tell us the answer to the 3 questions above, we'll be able to give you a better fix to the problem, IMO.

"Dissolved nutrients" is also a god basket term. "Dissolved minerals" is a tad more specific, but it could exclude DOCs (dissolved organic compounds) which may or may not contribute to algae growth. There are no hobby tests for DOCs. They should not build up significantly in FOWLR + protein skimmer, but can do with just biofilfiltration w/o sufficient water changes. DOCs can complex plenty of iffy ions that we do want in excess such as phosphates and nitrates. DOCs may also make tank stink and may be quite stable in tank water if not diluted out or at least down.

HTH