Breeding / Raising Apistos

[slimbolen99]

I'm starting to collect quite a few wild specimens and have begun to accumulate spawns. I have several questions regarding rearing fry in bulk:

1. What is the ideal temperature / pH / hardness?
2. To grow out 30 fry to, say, 1 inch, what size tank would be most appropriate? I am using 20H's right now (24" x 12" footprint).
3. How long does it take to grow fish out to 1 inch, with two 50% water changes weekly?
4. What is the ideal food?

I'm sure each species is different, but a generalization will help me quite a bit, maybe for each complex?

Thanks in advance.

Species I'm breeding now:
Apistogramma agassizi "blue"
Apistogramma agassizi "double red"
Apistogramma eunotus (Orangeschwanz)
Apistogramma iniridae
Apistogramma schwarzkinn/black-chin

 

[tjudy]

If the goal is to raise the fish as fast and as healthy as reasonably possible, with the only limiting factor being the space (take size) on hand (assuming your 20H tanks), here is what I do:

1. What is the ideal temperature / pH / hardness?

For fast growth I would push the temp to 80F. This means that you will need to increase aeration/filtration rate and probably step up water changes (see below).

2. To grow out 30 fry to, say, 1 inch, what size tank would be most appropriate? I am using 20H's right now (24" x 12" footprint).

If you are limited to 20H tank, then that is what you use. However, volume is not as important as oxygen, especially with bottom-dwelling apisto fry. What would do is start those fry (1/4" or so...) with the tank only 1/4 - 1/3 full of water. The lower volume allows you to feed less to maintain food density and improves oxygen diffusion into the water. As the fish grow and start rising into the water column to get to food you can increase water depth/volume.

3. How long does it take to grow fish out to 1 inch, with two 50% water changes weekly?

Water changes are the key. Two per week for FAST growth is too few. I use a variety of tanks (2.5, 5.5, 10, 15, 20H, 20L) and plastic bins for growing fry. Any of then that are under 10 gallons get 80% changes every other day. >/= 10 gallon get 50% every other day. I have limited volume of aged water, or the large tanks would get 80% changes as well. Aged water is the key. I use tap water that has been aged 24 hours in and open-air vat with an airstone and recirculating pump. I keep the vat at about 78F (sames as the growout tanks).

With 50% twice a week, assuming all other factors are optimum, I would predict it would take 5-6 months to grow MALE apistos to 1". Females take longer (and do not need to be 1" to be sellable, IMO). My water change schedule grows males to 1" in about 3-4 months.

4. What is the ideal food?

Baby brine daily. Micro worm or similar if I do nto have brine. I like to feed small amounts multiple times a day, so I will usually get two feedings of brine in the morning (if you put it in the fridge in brine it will live and not lose nutrition for a few hours), and after that I use microworms. Once the fry are 1/4" - 1/2" I start feeding grindal worms and chopped white worms. At 3/4 - 1" I will start chopped black worm.

I do not know of any food that will grow fry as fast or as well as live food.

That's how I do it.

 

[slimbolen99]

Thanks Ted. Looking forward to hearing more opinions as well. I'd like a nice collaboration here. Your thought on the water changes has my idea wheel turning...

 

[dw1305]

Hi all,
Good advice, one thing though is I'd grow out some fry to adulthood and see what happens at 80f with the sex ratio, you may find you have to play with the temperature to get a 1:1 mix male to female, or it may be possible to grow out half the spawn warmer and half cooler and get all males in one tank and all females in the other. You would expect that 79 - 80f should give a mix although tank water pH may also have an effect.

Having a look back through the threads for the species you are interested in.

cheers Darrel

 

[tjudy]

Temperature dependent sex ratios are probably set at the embryonic stage of development. I know of no study to support that statement, but I have not had a problem with sex ratios when raising fry at those temps. I spawn the fish in about 74-76F, and generally remove the fry after a week or so.

 

[Mike Wise]

Römer's studies on a large number of species of apistos show that sex it primarily temperature dependent and the temperature during first 6 weeks after spawning has the most important influence on determine sex. Therefore it probably is best if the fish are raised at 26C/79F for the first 6 weeks to produce a reasonably equal ratio of both sexes. Of course, pH is another influence of many (mainly blackwater) species.

 

[Apistomaster]

I haven't experimented a lot with pH and temperature to see if I could get even sex ratios but I did try to with one spawn from a wild pair of A. agassizi.
I used a hardness of 3 KH/GH and a pH of 6.6.
I kept the eggs and fry in an unheated container(Sterilite box shelf) with about 3" of water. I didn't heat the container so it was subject to room temperature fluctuations of 70 to 74*F. Only an air stone was provided initially to help keep the water fresh.
I raised just over 80 fry to adults and the resulting sex ratio was as even as one could ever hope to see short of exactly 50/50.
I think anyone who has raised this species can appreciate what a good ratio beween sexes this run was. Previously, I usually had a ratio of A. agassizi skewed in favor of the males.
I ordinarily wouldn't have ever tried incubating and starting out the fry of this species in such cool water but at least this once, it sure worked out well.
Once the juveniles were a few months old I raised them up in 82*F water.

 

[slimbolen99]

I guess my remaining concerns are regarding temp and tank space. Ted's information was informative, and I would like to know what other folks are doing as well...

 

[Bekateen]

Reviving an old thread, could someone please describe the current understanding of temperature- and pH-sex determination? I searched the forums here and I couldn't find specific answers.

Specifically, I've got Apistogramma agassizii. The adults are kept in a 36 gal community tank, pH about 6, temperature about 78F. The adults have spawned multiple times. Once the eggs are laid, I remove the mom and the eggs to a 10 or 15 gal tank with the same pH and temp settings. After three different batches of eggs, I've gotten only one male and all the rest females. From what I'm reading above, a temp of 78F should be giving me about even male-female ratios, so I'm wondering what pH effects exist for this species.

Thanks, Eric

 

[Mike Wise]

Römer's studies emphasized stable temperatures, pH, and other water values. It also put concerted effort into raise every egg (as close to 100% as possible) to a sexible fish. It's possible that your skewed sex might be due to more males dying before sexual maturity than females. Just a guess.

 

[Bekateen]

Thanks, Mike, for the perspective. Actually, prior to finding this thread, I had suspected that my skewed sex ratio was due to differential mortality or some other social effect. But after getting only one male in three (or four) clutches made me suspicious that it might be environmental.

So what are the currently believed values of temp and pH that yield more males in agassizii?

Thanks, Eric

 

[Mike Wise]

AFAIK, same as always - #1 temperature, #2 pH.

 

[Bekateen]

I'm sorry, that's not what I meant to ask. Which temperature ranges and which pH ranges produce more males?

 

[Frank Hättich]

Higher temperatures and lower pH produce more males Eric.

 

[Bekateen]

Okay, thank you.

Cheers, Eric