Small tank for baby angelfish - three questions


Hi all. I have six angelfish, two of whom are a bonded pair. I had those two first, and then added the next four. When I got them the four were all roughly the same size. Three of them have grown a lot, and the fourth one is still tiny. Moreover, that one tends to be quite isolated from the others. They don't attack him, but they don't include him.

One of the newer ones, since growing larger, has started to interfere with the bonded pair. He/She has become quite aggressive and recently nipped off the top of the dorsal fin of the teeny baby one.

I am looking at having him rehomed as I don't have a suitable alternative. But, in the meantime, I have a 9 gallon hospital tank that is cycled and ready to go. I was planning on putting teeny baby angelfish in there until he grows a bit (he never seemed scared or stressed even though he was isolated, but now he's hiding in a tunnel and I'm concerned about him) and until Nasty is rehomed. Nasty is too big for that tank - even short term - but teeny baby isn't.

First question: I'd like to put teeny baby in that tank for a few weeks until he is bigger. Will that be ok? He's dime-sized at the moment.

Second question: Once I've rehomed Nasty, I'll only have five angelfish. I have read that they should be kept in even numbers. Is that the case?

Third question: If they need to be in even numbers, I'd like to also put another dime-sized angel in the 9 gallon with Teeny Baby so that they can go into the large tank together when they're grown. It would be for three weeks, four maximum. Is that a viable plan?

The other alternative is to put Nasty in the 9 gal until he is rehomed and add another dime-size to the larger "home" tank but I am a bit concerned about Teeny Baby so I think he should be isolated anyway until he's bigger and his fin heals. Thank you!


How big is the main tank?

IMO a 9G is too small for any fish and certainly for Angels (how small they might be).

Nasty is probably only showing natural behaviour and if you remove him another might take over..


I've successfully quarantined small angels in a 10 gallon for a month or 2. Short term "Teeny Baby" will be fine in your 9, but you might as well start planning another tank or rehoming now.


question 1: I currently have 10 quarter to half dollar size in a 10 gallon tank that I'm quarantining to heal up and grow back broken ventral fins. it's fine short term, as long as you are doing really regular water changes and cleaning up the waste from them.

They will grow some, but they will hit a wall in a tank that small and it will stunt them. I've kept from fry to nickel size and heading toward quarter size in a small tank, too small really for as many as I was keeping. A handful to a dozen yeah probably up to quarter and beyond in size before it becomes an issue. You have to keep an eye on them and the other fish you have, you will notice the ventral fins not growing long once they hit the wall compared to the other fish of the same age in another tank.

Sounds like you got a runt in this group, which is fine. I'd suggest it goes in the 9 gallon by itself. He gets fed small meals every 4-6 hours if you can so he can put on weight and size. the other fish that are bigger, keep them on your routine feedings. the extra feedings will allow him to grow at a faster rate and "catch up", he will eat more often and poop more often, but the extra absorbed will go to body mass, which will go to growth. Somewhere around quarter to half dollar size he'll need to be in a bigger tank, and hopefully by that time the extra feedings and no food competition or shyness will have him if equal size and out of his shell and he can be reintroduced to the group, bigger, stronger and more sure of himself.

question 2: Even or odd numbers don't matter at all. if you are looking for a pair, you'd want to keep 6 juveniles and there's a high chance at least one fish will be a female. other than this, odd or even doesn't matter. 1, 3, 2 or 4, it's all the same thing. when they mature is when you have to watch out for problems.

question 3: yeah, another in with him would be fine, BUT just recognize another fish is competition for food, and this little guy is likely the low man on the totem pole and would get pushed off food. If kept alone he can be comfortable, eat as much as he likes and gow in size strength and confidence without worrying about other angels for a while.

the more aggressive one, that is most likely a fast grower and will be a dominant male and already attempting to assert his position. if kept he will likely wind up being the larges of them all and outgrow your older male, and if he's acting like that already, he's likely already got his eye on the mature female and looking to maybe slip in there one day when he's bigger.
That all said, he's likely a really good subject for breeding later on if he has color qualities you like, if you don't intend to use it as a breeder though he's going to be nothing but trouble as he matures and not worth the effort and should be rehomed.

And heres my qualifications... Yes I'm aware it's overstocked it's intentional and I can handle it, just saying I've been dealing with angels for a few years now, and breeding them for about a year. 4 mature males, all of them are non-dominants, 30 near half dollar size juveniles.
the guy on the bottom left of the tank is likely going to be my dominant male of this group he's already started acting up and he will pass up the mature males in size one day. he will likely need to go. I watch them for hours each day, trying to identify behaviors that would indicate trouble and waiting for the females to mature so I can then separate the dominate males and the females out of this group for possible pairs with unrelated to them angels. domimnant males are good for breeding, thy usually get the most food, grow the largest and have good genetics, but they aren't good community fish. A female can handle them and they can take a beating that a female can dish out also. Pairs really need to be kept alone.

I wish you the best of luck!


Thank you so much! That's an awesomely thorough answer :)

Sadly, Teeny Baby died (well, I had to euthanise him). He really was the runt, he wasn't growing, and I took him out of the tank as his damaged fin had developed rot. Found the poor little dude the next morning swimming around frantically, upside down and around, the rot had spread quickly, so I just put him to sleep as gently as I could (clove oil).

One of my other guys is a bit bolshy too and has a go at Nasty from time to time. I suspect they'll sort it out themselves but I just think that Nasty is a bad apple and whilst I know that if I remove him it could mean that another just takes over, I don't think that will happen. I think he's the one that riles the others up. So he will be rehomed. He's a leopard and not all that attractive to me so I don't want to breed him.

I actually just purchased another pair today. They've been at my LFS for just over two weeks and are a decent size. They're *definitely* a bonded pair already so I was kind of concerned that someone might come along and take one of them and split them up. So, yanno, what could I do? :D

I'm going to put Nasty in the hospital tank until he's been quarantined for two weeks and then my LFS is going to take him off my hands - I didn't actually get him from them but my guy there, Alex, is awesome and always happy to help me out.

I'm sad about Teeny Baby (aka "Moose") because he was so sweet but the others grew so fast and so healthy and he never did. Poor little guy.

Similar Aquarium Threads

Fish Newbie
  • Question
75 Gallon Tank Angelfish Surprise
  • Question

New Angelfish Threads

Top Bottom