Some of my angelfish won’t grow

[JuiceBox52]

One thing I’ve noticed in my 210 gallon is that some of my angelfish are still only a little bigger than dime sized after months, while some are quite large already. We got them varying from dime to quarter size, and most are growing steadily, but some haven’t seemed to grow at all. We’ve tried target feeding, but even without target feeding the small ones are visible eating the same as everyone else, not being bullied away from the food or anything.

Anyone got any ideas as to why the stunted growth or how to help them grow? The tank is not over crowded and they are fed plenty

(Finger for scale)

 

[Naughts]

Sounds like you’ve ruled out space and food issues so could it be stress?
Aren’t there hormones or pheromones released by dominant fish that restricts the growth in others? You may need to do big regular water changes to dilute the hormones.

 

[JuiceBox52]

Sounds like you’ve ruled out space and food issues so could it be stress?
Aren’t there hormones or pheromones released by dominant fish that restricts the growth in others? You may need to do big regular water changes to dilute the hormones.

I do recall reading something about that, but had completely forgotten that as a cause! I usually only think of pheromones in agressive or fish stressed due to too small of a shoal, but that sounds like a great idea to try

 

[GaryE]

When you say you got them young - I'm assuming you didn't breed them?

I see different eye sizes. Huge eyes and small bodies can be an indicator of poor nutrition at the start of life - a kind of starvation stunting. It'll happen with a combination of infrequent water changes and poor feeding (or, overfeeding producing pollution) very early on. Could that be the culprit?

You have several different linebred types. Are there differences between the colour forms in terms of growth?

 

[JuiceBox52]

When you say you got them young - I'm assuming you didn't breed them?

I see different eye sizes. Huge eyes and small bodies can be an indicator of poor nutrition at the start of life - a kind of starvation stunting. It'll happen with a combination of infrequent water changes and poor feeding (or, overfeeding producing pollution) very early on. Could that be the culprit?

You have several different linebred types. Are there differences between the colour forms in terms of growth?

Correct. I got them from a breeder in my local aquarium society.

Because I didn’t have them from birth nutrition issues could certainly be a factor I just don’t know about

It seems all the yellow ones, or at least most have grown a little better. But as for the black, blue ones and the more silver ones, it seems to be a mix of small, medium and large (in comparison) for each type. Some tiny black ones and some bigger black ones etc

 

[GaryE]

One of the dangers with home bred fish is if we hold on to too many for too long, we get similar effects. If you get big spawns of angels and try to raise them crowded, you'll create disasters for the fish. My black and silver angels in the past grew very fast, but that was because I screwed up a lot and never ended up raising as many as I wanted to.

I visited a local angelfish company once - a man struggling with alcoholism who had stopped drinking was maniacally maintaining 150 20 gallon tanks in his basement, and selling enough angels to make a living at it. He also worked 16 hours days to do, in desperation to stay busy and dodge his addiction. He was always doing water changes, it seemed. You could only talk to him when he was slinging hoses around, draining and filling. He did 50% daily on his tanks (his local water wasn't metered...). He would raise small numbers of angels per tank, and got them out there quickly before any stunting could start.

I played at raising angels in 30 gallon tanks, largely because I liked watching how their bodies would take on the angel shape. The problem with raising too many and ruining a lot of them as a result is something beyond angels that I've seen with all Cichlids.

 

[Uberhoust]

Just some observations watching a number of Angelfish grow in my tanks. A few years ago I raised a few hundred angelfish from eggs to sending them to the pet store. My observation is with the batches I raised with their parents were much fewer in number, but generally more consistent in size and form. As I transitioned to collecting the eggs and raising them separately, I found that the batches were significantly larger, 3 to 5 times, but I also noticed that I had a lot more "runt" survival. I still have a number of these runts because they did not grow to a reasonable size when I was taking a batch to the store. They are nice but at 3 to 5 years old they still have not attained the same size as their parents or other siblings, and some have fin defects. I suspect that as we breed for features like panda, blues, smokes etc. that we are focusing on a number of traits that really only appear with some recessive genes. My thought is that excessive inbreeding, and selection of recessive traits within the angel fish being sold now results in more of what I would consider poor doers. There is some hope though, in my poor doers I have seen constant growth, just slower than the others, though none achieved sizes in line with their more robust siblings they still are growing, whereas the faster growing ones have really stopped growing some time ago. In a wild environment slow growth will likely make the odds of you being food higher, but in a controlled environment slow growth just means you are smaller longer.