Well Ian, that might just be where your bioload is set. Also remember, as nitrates get lower and lower, it becomes more and more difficult to remove them via water changes. 20ppm without any real nitrate-reducing equipment isnt anything to be worried about. If I were you, I'd add a few more corals to help filter feed and process nitrates
so with 150 watt of lighting on a 30 gal tank can we have hard corals? if we stick them near the top of the reef?
wich green one we wanted?
(not that it matters as i can`t remember the names of any of them
yea thats the one........
still don`t know the name of it
Lol, you guys are awesome 8)
You can for sure keep any LPS under a 150watt halide and you could also succeed with most SPS if you keep them at the top of the rock stack. Remember that SPS prefer very high current while LPS are usually more of a medium flow coral. It is possible to blow the flesh off of an LPS if you stick it right under a point-jet of a powerhead, but pretty tough to really do the same to an SPS