how many new fish at once??

[reefobsessed]

Is there a rule of thumb about this?? My new 120 has 9 fish all small under one inch and I am only going with small non aggressive fishs. I have 2 occ clowns, 3 high fin cards, copper banded butterfly, barletts anth, bi color, I want to add 2 barletts, 2 fire fish, 2 purple fish and a small hippo. Can I safely do it all at once?? my water levels have never been better....

 

[Gauge]

The only rule of thumb that I've heard regarding this is that you should not add more than 50% of your total fish length at a time. So, if you have 10 inches of fish, you shouldn't add more than another 5 inches at a time. Of course, when you have a very small stock of fish in the tank this doesn't really apply. I only have a 42 gallon tank, so when I was stocking the tank, I would try to keep it down to one fish a month or so. (I wasn't very disciplined about this, but I tried!)

 

[reefobsessed]

I am doing an overnight order from the doctors and with the acros, hermits, zenia, & 3 clams I really want to get the additional fishes. I just dont want them to die. I think with 120 & 30 more in sy ref. I should be ok but want to be sure..

 

[jamal-188]

I"m not expert but I think that many fish at once may spike your ammonia/nitrite levels a bit until your biological filtration can catch up. Are you going to put them in a Q tank or right to your display?