How many fish can I have

Alex Johnson · Nov 13, 2018

So I have a coral 29 gallon Biocube. It has been established since the beginning of June 2018. It has a refugium and a protein skimmer. For fish I have 2 clowns and 1 lemon. For coral I have a blasto with 1 head, a single mushroom, a small/medium size leather coral, a small/medium size frog spawn coral with 2 heads and some a small zoas. I wanna ad more fish. Such as a Bangai cardinal, a royal gramma, a fire fish goby, Midas Blenny and possibly 1 more fish. Would that be to much for a 29 gallon tank?

Old Fritz · Nov 13, 2018

I mean it really depends on who you ask. However I believe a lemonpeele angel is asking for problems in a 29 gallon. However I believe that you could do the clowns and the other fish listed without any problems as i've kept more similar sized fish in smaller tanks, you'll just want to be sure to keep an eye on your water quality for when you need to do water changes, obviously the more fish you add the more water changes you'll have to do

Tastee · Nov 13, 2018

I’m afraid I would say yes. I have about what you are planning in my 65g and that’s all I’m going to add.

The bio-load you can support depends on your bacteria surface area (LR, Marine Pure etc) and your nutrient export strategy. If that is respectively lots and effective then higher stocking levels can be supported.

The other issue is the physical space, so you need to research your fish well. Most species are territorial so each needs to be able to find it’s ‘safe space’. Most need somewhere to sleep, how many spots are there in your tank? Some need large linear distances to swim (e.g. Tangs).

Whatever you do I do recommend you add fish gradually. I intentionally added the bulk of mine fairly quickly, over a 3 month period (but generally 1 at a time), and whilst that worked in terms of having a number of juvenile fish which all grew up together and sorted out hierarchy etc, it did give me a GHA issue that took me months to sort out. I was learning about my nutrient strategy at the same time which was part of the problem.

cromag27 · Nov 13, 2018

not too many at all except foe the lemonpeel as previously mentioned. they can also nip at coral. however, i would not add all those new fish at one time. and be prepared to change a lot of water. that’s a big bioload.

Tamberav · Nov 13, 2018

So 8 fish in a cube tank? Too much imo....not enough space. You have peaceful fish mixed with semi aggressive ones and will likely run into issues. Midas blenny's sometimes pick on firefish too....in my case every Midas I had in a nano got big and turned into a real jerk to any fish he saw. When he started grabbing onto my Picasso clowns..he got the boot.

pshootr · Nov 13, 2018

According to most conventional rules in the hobby. You should expect to keep approximately four 3 inch fish in a 30 gallon tank. Of course as mentioned already. Aggressiveness, places to sleep, and the degree of maintenance you are willing to do, will all play a part. Where it concerns keeping more than that number.

You probably could keep up to six-eight fish in that tank, but that doesn't necessarily mean that you should.

pshootr · Nov 13, 2018

If you were only allowed to flush your toilet two times a day. And there was one bedroom. How many people do you think should live there?

I know this is kind of an outlandish analogy. But it is quite similar actually.

[emoji23]