So I just hooked up my 2217 a few days prior and was in total awe of its beastly ways... and thus my eyes were opened to the world of over filtration, ahhhhh so refreshing
What do you do when you've got a filter that seems to have as much water in it as your tank you say? Of course you go to the LFS to buy fish!
6 neon rainbows and 3 GBR's later.. Nitrite spike
I had levels .25-.50 ppm it was nutz.
Since I experienced crazy stuff while my nano was cycling, i kind knew what I had to do:
- initial waterchange to protect fish (dilute levels)
- raised spraybar to super oxygenate water at night (foster bacteria growth)
- bought an entire tank of hornwort from the LFS (absorb nasties)
- open the flood gates on the 2217!
Result: levels yo-yo'd for a couple days, by the 3rd day it was regular scheduled waterchange, rinse and repat. One bacteria bloom later (cloudy water) levels stabilized. [I had to do this twice to my tank btw... tank fully cycled by the 6th week]