Backyard Aquaponics
A place to discuss aquaponics

You've probably read Mike's Hatcherymanual.pdf (top link on cherrysnapper.com) He recommends a 2 gallon pot facing one wall of an aquarium for the male -- and 5 or 6 females. Amazing how I get much more out of a book once I have some practical experience with the subject

And I bought a big fine-mesh aquarium net to catch my fish with. It works well to catch them and then hold them while I inspect or do surgery.

I use a net like that for my barbs. They've grown to almost the size of a good sized piranha... then again, every time I introduce smaller fish to the system (Except Angelfish) they are devoured by the barbs.

I have at least 100 baby tilapia now!

congratulations Grandpa

I took the mother out because she looked like she was eating the occasional baby. From what I've read, once the babies are free swimming, they don't benefit from their mother's care any more. And I'm not sure if I'm feeding them enough, but the fry seem to have bulging stomachs. I'm guessing that my aquaponics aquarium (that I rarely clean) must have quite a colony of microscopic life. I've been crumbling up goldfish flakes periodically and the fry seem to eat some -- they don't crowd around like they are starved though.

do you seperate fry to grow them to size ems? Or allow them to be the "circle of life" that elton john sings about?

I'm hoping that I'm included in these Tilapia's circle of life -- I'm planning on eating them -- once they get big enough -- right now I could probably fit 200 inside a teaspoon.

We tried using fish food flakes, wetting them and mushing them in our fingers and putting them in with the fry. Worked OK, but difficult to mush them up evenly.
Now we use floating fish food balls and soak them overnight before putting some in with the fry and mushing them between fingers. Easy Peasy!
Only buy one sort of fish food now - 3 mm balls. Even the goldfish are taking them whole.

We use plastic ice cream tubs in 2 or 4 litre sizes, cut windows out and attach fibreglass fly wire over the windows (Tayo sews them on with nylon thread)
We have 3 of them in the aquarium now each with 30+ fry in them.
today we transferred our oldest fry from one of these into the aquarium. There are 13 (now I suppose should be called fingerlings) which are about 20 - 25mm long. The girls, including mother, are the only other Tilapia in there and are not eating them (yet?). They didn't bother the bristlenose catfish of the same size, so we thought that they would be OK.

Will advise any developments.

emsjoflo,
All the best with your Tilapia.

Happy New Year,
Tony

I used a mixture of cooked egg yolk and brewer's yeast to feed my littlest fry. Mix with water to get a smooth paste and rub just a small pinch between your fingers in the tank water to disperse it for the fry. The extra protein is good for fry, and they quickly graduate to powdered flake.

One of the females is still holding her brood in her mouth. -- her tank is in the garage and is a bit cooler 78 F while the one inside is running at about 86F. Would the temperature make that much difference or is she just more maternal? Should I open her mouth and dump the fry into the water or let her take care of them?

Let her be. She'll spit them out when they get too big. Temperature definitely makes a difference in growth rate. Tilapia grow best in the mid-80's F.

Her throat is puffed out like a bulfrog's. She let one of the fry out and it was bigger than the ones in the other tank. But I'll trust that she knows what she is doing.

Mum knows best.
Its too cold out there, put a jumper on. Wash your hands before eating, etc, etc.

Speaking of cold... It was -10F this morning. The doorknob on my garage door was frozen (due to the high humidity inside -- with 600 gallons of 80F water being constantly aerated and pumped through growbeds)

It is cold enough that I'm having second thoughts about trying to run my greenhouse year round.

But I would like to be able to get a car into the garage next winter....

On a more positive note, I see that one tank of Tilapia fry have almost finished their first 4oz container of beta flake -- most of which was delivered by the automatic fish feeder I bought for $12. (after all the dire warnings about moisture, I'm thrilled that it has worked without a problem even though I dropped the whole thing into the aquarium -- food and all)
I went to the LFS to buy some more tiny flakes, but I could not bring myself to spend $6 for another 4oz that might last a week. So I borrowed FIL's coffee grinder and reduced the size of some goldfish flakes and some of my fish pellets. It worked great. By my calculations, I saved about $9 in about a minute.

I've never liked coffee anyway.... The smell of it brewing is bad enough.

Anyway, most of the babies in the other tank disappeared (eaten by sibs? sucked into pump? killed by parasites?) So I put my one remaining female back into the tank (to keep her from killing any other fish during her post-partum depression) I thought she had killed off the babies but I saw two in there the other day.

Before church yesterday, I netted on the the larger males and put him in the tank with her. I'm hoping she learns from her prior mistakes and raises a brood to maturity this time. I read somewhere that some Tilapia mate for life and will not deign to spawn with anyone other than their chosen mate. I'm hoping these two aren't so picky.

Perhaps the trout feed I'm feeding the tilapia is too high in protein (I think it is about 40% and contains fish meal) I've read that high protein feed can make Tilapia more aggressive ( I wonder how it makes them taste?)

Perhaps the fact that the aquarium is on the floor in the "schoolroom" is disturbing to the fish. My 2-year-old likes to "feed" the fish so some foreign substance may have entered the tank. Though I don't see why fish would be bothered with crayons, animal crackers, doritos, or small pieces of paper. Perhaps the activity and attention bother the fish.

pH was close to 8 so maybe it is too high? I'll test for ammonia, nitrites, and nitrates when I get home tonight. I haven't vacuumed the gravel recently and there is some nasty algae on the back -- could some types of algae be poisonous to fish?

I crumbled goldfish flakes to feed these fry. And I noticed quite a few with long tails of poop. Perhaps the food constipated them? Perhaps the tank was too large and the fry couldn't find the food? Perhaps I didn't feed them often enough (I didn't put an automatic feeder on this tank because I was afraid the little man would think it was a toy......

Perhaps the mother and father were too closely related and the fry were genetically inferior (two got big, at least 4 or 5 seemed deformed)
How does a person "tag" fish? I'd like to be able to number my breeders instead of trying to identify them by color and size. Color and size are relative to the other fish and when I go to catch them, the water gets murky and it is hard to compare....

Perhaps the pump destroyed some. I took the sponge filter off of it when I had 11 adults because it would foul in a few days and reduce the flow to almost nothing. I watched for any getting sucked into the intake, but none of the fry ever went in while I was watching. Quite a few swam close and then swam away from the pump -- I think baby fish must have an instinct to swim upstream. and I looked for evidence of fry in the growbed -- nothing.

All I know is that the fry in the tank out in the garage stayed in Mom's mouth at least a week longer -- when they came out, they were at least twice the size -- and they are all about the same size and have outgrown even the largest basement fry.