Minimum size for grow out tank

[raymond82]

Hi,

What would be the minimum size for a grow out tank for Apisto fry? Let's say the maximum amount of water changes I can do is one a day and the fry should stay in the grow out until they can be sexed (and sold).

 

[Mike Wise]

How many fry are you thinking about?

 

[raymond82]

Ah, that question makes sense. So far the biggest batch of fry I had was around 50 but usually I think I have around 30 fry in a batch.

 

[Mike Wise]

For 30-50 fry I'd use a 30 gal. long 36x12x16"/90x30x40cm tank or something with a similar bottom surface. I would do as Ted Judy recommends, however. Start the small fry in a smaller tank (less effort to find food, etc.) and as they grow put them in a larger tank. Also make sure that there are lots of hiding places as they mature. 4"/10 cm sections of PVC pipe work well for this.

 

[raymond82]

That's a lot bigger than I expected, I really need a dedicated fishroom! Right now I have the smallest fry in a 10 gallon, I once grew around 40 fry in a 15 gallon but I had the feeling that was very much on the edge in terms of water quality. Besides, the fish grew really slow and I traded them when they were sexable but not yet at a good size for selling.

 

[Mike Wise]

... I once grew around 40 fry in a 15 gallon but I had the feeling that was very much on the edge in terms of water quality. Besides, the fish grew really slow and I traded them when they were sexable but not yet at a good size for selling.

That's to be expected. Water quality goes down really fast in small tanks as the fish get larger - and pass more waste - without increased water changes. In this case, the old saying that environmentally conscious people hate actually is true: "The solution to pollution is dilution."

 

[raymond82]

"The solution to pollution is dilution."

This is a good rule to go by, in general but also in cases when the amount of fish grows over my head the only thing left to do is lots of water changes.

Fish keeping is difficult for a number of reasons, but I think the most difficult is to have the discipline of not having too many species. I ran into trouble because of having too many species and they all had fry. The reasonable solution would be to have less species but that's more difficult than it sounds!

 

[Mike Wise]

... I think the most difficult is to have the discipline of not having too many species. I ran into trouble because of having too many species and they all had fry. The reasonable solution would be to have less species but that's more difficult than it sounds!

I agree, but it is so hard to do. I try to keep 2 breeding tanks of special species going at the same time, so that limits me to 5 - 8 species. After returning from Peru last Fall, I have 12 species going. Now which ones should I get rid of???