How much is too much for fish in a new tank.

[sfsuphysics]

Ok my 135gallon tank is almost finished curing (and cycling) with uncured live rock. ammonia is down to 0, nitrites are down to 0.5 and nitrates hovering in the 20 range. Now in my 10 gallon I have a blue damsel & a tomato clown, which I'm told can be rather agressive, they dont seem too aggressive of course it might be that both are aggressive so neither will back down hence no problems *shrug*. Anyways it was suggested that green chromis would be a good fish to school, 6 or so, as they are very fun to watch so it sounded like a good idea as I figure they wouldn't get picked on either in a group. Now I've never dealt with a tank of this size so I dont know if that's too much at once or what, any opinions?

[nevpugh308]

Personally I'd wait longer before adding any fish .... you yourself say it's "almost finished", that means it ISNT finished. Your nitrates are a bit high, and there's probably all sorts of other levels which are too high but you can't see. Just IMO of course.

[nanocat]

Depends on whether you fall into the "all life is valuable" camp, or the "chromis are $3" camp :D

Personally while I would never "cycle" with a fish (cruel IMO), I wouldn't have a problem buying 3 chromis @ $3 ea. with nitrates @ 20 (and going down). Is it possible they could die, yes, it's possible, but highly unlikely (with proper acclimation). Then after about 4 days, I'd add the other 3. I'd be reluctant to add 6 fish at once, but then you do have a 135g. It's your call.

I probably wouldn't be willing to buy a $70 fish until my nitrates were lower, and the tank more stabilized. That's just me.

[TheUltimateNoob]

patience is the key. if the cycle is almost finished. why not just wait a few more days? what's the rush? the cycle will be over soon and it will be completely safe to add fish. even if chromis' are only a few bucks, just wait.

[sfsuphysics]

Well I am waiting for the cycle to be done, just want to get some ideas. I didn't mention this but I got two 32 gallon rubbermaids filling with RO water (about 80% full) to one big water change after my rock is cured & tank is cycled.

I am *NOT* using fish to cycle, the cured live rock is being used to cycle.

[MichaelD]

Oh a chromis usually do better in odd groups. 5 or 7 works well

[sfsuphysics]

odd groups? so boy girl boy girl thing doesn't match up?? :)

[bertoni]

Personally, I'd add three or so Chromis at a time, once the nitrites, at least, were zero. There's a great thread on tank maturation in the coral forum, as a sticky note at the top, if you want to know some reasons to wait longer.

I'm personally somewhat skeptical about the odd number suggestion, but I'd be interested in hearing more.

[Reefmedic79]

I believe Chromis are harem fish, meaning one Male to a group of females.