overcrowding question

mach1john · May 5, 2015

When should I start to be concerned about overcrowding? I have a 75 gallon with live rock and a 20 gallon sump. I have a protein skimmer that really works well. For live stock I have:1 blue hippo tang, 1 yellow tang, 1 cardinal, 1 keyhole angel and 2 clowns. I would like to add 3 green chromis. Any thoughts?

declanisadog · May 5, 2015

Prepare to be jumped on about the tangs. Regardless, if they are all small and you have good filtration, three more chromis shouldn't be a problem.

mach1john · May 5, 2015

Had the tangs for a while now. They get along fine.

jofost1216 · May 5, 2015

Its not about them getting along but there are going to be those tree huggers that tell you you're awful for keeping 2 tangs in a 75. Lots say they shouldn't be in anything smaller than a 125. They swim an average of 5 miles a day. As long as you stay up on water changes and have enough hiding spaces they'll be fine. i know someone with an elos 70 with about 20 or so fish. Does 50% water changes weekly and faithfully. I have a 56 gal and a tiny blue hippo but i get a new one every year or two once they hit around 3 inches. Just keep an eye on them and make sure they are healthy.

Trex · May 5, 2015

Tree huggers?? Lets try to keep this civil please.

IMO/E, a 4 footer is too short for an P. hepatus --- they can/will get over a foot long. So, in the long run it would be better off in a longer tank.

As for the 3 chromis, I personally would skip them. Not for over crowding, but for their tendency to pick each other off until there is only one left.

Pete polyp · May 5, 2015

I don't see any problems with having that many fish in a 75. If the system can handle the bioload then go for it. I have 12 fish in my 40 and plan to add more

NanaReefer · May 5, 2015

jofost1216 said:
Its not about them getting along but there are going to be those tree huggers that tell you you're awful for keeping 2 tangs in a 75. Lots say they shouldn't be in anything smaller than a 125. They swim an average of 5 miles a day. As long as you stay up on water changes and have enough hiding spaces they'll be fine. i know someone with an elos 70 with about 20 or so fish. Does 50% water changes weekly and faithfully. I have a 56 gal and a tiny blue hippo but i get a new one every year or two once they hit around 3 inches. Just keep an eye on them and make sure they are healthy.

Tree huggers? Are you referring to those of us who choose not to keep fish like you do?

Trex · May 5, 2015

There is more than just bio-load/filtration to consider when adding/keeping fish.

eatbreakfast · May 6, 2015

As it grows be prepared to move the Hippo tang. Beyond that, the tank can handle the chromis, though some have had multiples pick each other off, this has not been my experience.

Factors to consider for stocking include bioload/filtration, fish size and habits, as well as tankmate aggression.

randyplank · May 6, 2015

I agree with this. I consistently end up with a single Chromis.

Trex said:
As for the 3 chromis, I personally would skip them. Not for over crowding, but for their tendency to pick each other off until there is only one left.

haleyf1024 · May 6, 2015

I'm going to +1 on just being prepared to move the blue once he gets too big or gets a little aggressive. I would personally skip the chromis unless you can find some healthy, quarantined ones or you QT them. I made the mistake of getting 5 green chromis and had them bring uronema into my system. Lost all 5 and about 5-6 other fish. The chromis are notorious for carrying uronema, and I personally won't risk bringing more deadly parasites into my system again. If you QT them, you could get away with it. Just expect them to pick each other off until 1 is left.

Mauger's Reef · May 10, 2015

I have 3 chromis in my 60. Great schooling fish, spawn almost every night, get along with all fish in tank, and add great color and movement if they're happy and fed the right food. Never had a problem with aggression.

4FordFamily · May 10, 2015

Geez this thread went awry. I overstock the snot out of my tanks. It works out 99/100 and when it doesn't, just have a fish trap ready to remove problem fish. I keep large Angels together, several tangs in same tank, etc etc.

I also skim for 3x+ my water volume, have many other means of filtration, feed a variety of very nutritious foods, and do regular large water changes. Some would still have a stroke if they saw my tanks.

WindeyD · May 10, 2015

I will not pile on the tang issue, but it has also been my experience that I always end up with the one single chromis as the others slowly get picked on to their demise. Off to hug a few trees!!