so heres a odd question.

All my tanks are crystal clear with great bio eating on Ammonia and Nitrite 24/7 never a trace no matter how long I wait on a water change. But we are not talking about that we are talking about Bio waste in the form of Nitrate which no bio in an aquarium can eat, and if you could ID them you'd probubly also win the Nobel Peace Prize. Plants yes, Algae Yes, $1200 nitrate filter yes. Other then that nitrates build in the aquarium build about as fast as pooping in your pool would make you stop swimming in a week.

Even though I can see it my Angels are my indicator. They can take 2 weeks but once Nitrates get past 20 PPM their fins start to rot. It takes 2 weeks for my tanks to reach 20-30 PPM and its defiantly time to flush the toilet.
 
the tank that never gets changes is my uncles and i thank its a twenty long, as far as my tank i get it tested and every thing is fine, and like i said its even got the marine biologist i know completely stumped. but i do need to get a new gravel vac because the bottom of my tank can get nasty, i had a good gravel vac but a friend stepped on it on accident.
 
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