[Delphinus]

One week later and the effluent still reads 13ppm so I'm going to try slowing it down somewhat in an effort to get it to read zero (so that I can increase the flowrate and have it attack the "ambient tank nitrate level").

In the space of one week though my tank has tested as low as 21ppm NO3 (which I thought was pretty good) and as high as 31ppm. In fact, it tested 21ppm 3 days ago and yesterday it tested at 31ppm, so a full ten point increase in two days.

I'm at a complete loss to comprehend such a jump in nitrates. I haven't fed my anemone at all in a couple weeks, and I've been lightly feeding the one fish in there (a juvenile S. virgatus rabbitfish). His tankmates are 2 cleaner shrimp and 2 peppermints, plus some snails and 2 urchins. This is a 110g tank so I would consider this to be on the low end as far as bioload is concerned. The big question mark is the anemone ... near as I figure it is some kind of weird nitrate producing beast but I would have thought that output would correspond to input but it seems as if it doesn't matter if I feed it lightly or feed it heavily, the nitrate is always there.

I am starting to think that the tank needs a major overhaul.. maybe a larger sump so I can increase the rock volume, and maybe a skimmer overhaul or upgrade. I guess there's the possibility of testing errors on my part but it seems suspicious that I'd get a reasonably steady level on one thing and at the same time such a wild fluctuation on the other.

I think this is just a weird tank to be trying this experiment on. Something is just not typical/average here.