Backyard Aquaponics
A place to discuss aquaponics

The fry will definitely need hides with 17 fish in 100 gallons! Holy Smokes! That's not conducive to a nursery!! You'd still be lucky to keep half of them. I would do some careful monitoring to try to pick out 1 non-violent male and 3 larger females. Get them alone in the 100gal tank. (I have 1 male with 2 females in a 50gal 3-foot tank. It's juuust enough.) You can watch behavior to sex them (that's my best method), but also, you can examine private parts and mouth size. I really see in mine that males have wider mouths than females.

Give the male a love shack (large pot turned on its side), and give the females hides (lengths of 4" PVC) at the other end of the tank. Check all females every day. When you see a female clamping her lips together, puffing her throat out, and declining food, she has eggs. In about two weeks she will be ready to release them. My white tilapia get heavily marked with black bands, especially across the face at this point. Here's the tricky part. You can either put a divider in the tank to keep the others away from the fry, net the male and other females out, or if you are sure the fry are free-swimming, net her out. She may well spit the fry in the net, so you need to be sure the fry are ready for independence.

I've hauled fish twice recently with no problem. On the last trip I had 4 adults and ~80 fingerlings. I'd estimate the total weight around 8-9 lbs. I have two 55gal plastic drums. I just laid them on their sides and cut doors in the top for access. I was able to put about 40 gallons in each of them and got home with about 35. I used an air pump powered by an inverter plugged into my cigarette lighter. It it rated for an 80 gallon aquarium and it supplied both tanks. I made a small bunk out of 2 X 4's for the barrels to lay on so they wouldn't move around.

The drive was about 2 hours AND the fish stayed in their tanks overnight when I got home. The air seems to have done the trick. They were all healthy. The ammonia level was around 1.0 in each tank. Anyway this seems to be a decent way to haul them at least for short distances.


And Janet, thanks for this great thread. I now have TWO females with eggs in their mouths by using your tactics! thanks.

Awesome, Jazz!! Let us know when you have free-swimming fry!!

I've been watching my larger female get friendly again with the male. It's her turn to spawn, and she's been hanging out with the guy. Patience....patience....

I didn't see this anywhere else on the forum, so I hope it's not a repeat.

http://rdaquafarms.com, R & D Aquafarms ,in Oshkosh, WI, sells tilapia in small amounts.

They also sell fish pellets in small amounts (by the pound, instead of 44lb bags), but the feed is really high in protein, 40-50%. That's too high, isn't it? I was eying it for my catfish, but I think that's too high for even catfish.

I'm going to e-mail them and ask what they're made of.

Tilapia fry range from $0.25 - $0.50 depending on the number, and 4-5" are about $2, depending on the number ordered.

Does anyone have experience with this group?

Hadn't heard of R&D before. I guess somebody better try to get an order from them and test them out for the team.

I feed my fingerlings 45% protein flake, and my larger tilapia a 35% protein floating pellet. While that protein level is fine for the fingerlings, I felt that 35% was a touch too high for the larger fish. I would have used 30% if I could find it. Nonetheless, the fish are doing well on it. Dave D tried some 40% protein with his tilapia, and I think he's going back to the 35%. I'll let him comment on the results of that trial.

The lower protein (35%) is also what is more suitable for catfish. Below a link tothe brand food that Dave and I use, and they have good writeups on content and suitability for different fish. I use the Bronze floating pellets.
http://www.zeiglerfeed.com/html/finfish.htm

Janet I have had not luck sexing the fish. I had one female for certain, but she may have been sucked down the drain because they knocked the drain screen out and then one decided to hide in the drain hole and got stuck. What if I just put all of them into a 300 gallon tank? But then I have already ordered 200 more tilapia. Someone said if you squeeze the belly of the fish if they are female eggs will pop out. Perhaps that might work to find the females?

I thought I already told you guys/gals how to sex any animal. In this case you simply place a bottle of beer in one corner of the tank and Italian shoes in the other,,,3 nano-seconds later yoiu have almost perfect seperation ( almost perfect but as you know there is always one "different" in every crowd).

Actually manually sexing is not perfect and most are happy if they get 90% correct......,here's a link thatshows what you are looking for:)

http://aquanic.org/publicat/usda_rac/efs/srac/283fs.pdf

If you are even in Texas do come by and demonstrate this

I have tried and was wrong. I cant see anything different.

Dan ,rather than squeezing looking for eggs , squeeze and look for "milt", white fluid that comes out the male. I've seen this method used for other fish.
I grow Tilapia by the tens of thousands but grow males only , sorry ladies but female Tilapia are definately inferior in growth rate.

I was taught recently to use a little food coloring. Wipe just a tiny bit on, let it sit for 15seconds or so and then wipe most of it off. It will help bring out the detail.

Dan,
When the females are very near to laying eggs, they will also be pink in their private area. Of course, that's easier to see when the fish are white to start with.

I took my best guess when sexing by examination. I was perhaps 2/3 correct. Honestly, I had to keep swapping fish in and out of the breeder tank for 2-3 months before I got a breeding suite that wouldn't kill each other and actually contained the correct ratio of girls.

I'd say to take your best guess and put 1 male and 3 female breeders in the 100gal tank. Loveshack and hides as described above. Move the rest to the 300gal tank. When you get the 200 fish, add them to the 300gal tank. Monitor the breeders, and if after 3 weeks you don't have someone with a mouthful of eggs, swap fish around.

btw Dan, 200 fish in 300gals of tank sounds very aggressive. Even more-so since I think this is a virgin system. (Actually, come to think of it, I wouldn't grow out 200 fish in 300gal in a mature system either.) Even if you have 600gal of growbeds, I would cut your fish order in half if you are going to grow them all the way out in there. And start eating fish at 3/4 pound. Otherwise, you'll just have a giant fishkill after having gone through a number of HSM's.

I have 700 gallons of fish tank, 420 gallons of sump and 1200 gallons of gravel grow-beds..

The 200 new fish I am getting will be smaller fingerlings. Which I will be giving a way a few tp the brother-in-law in hopes of getting him hooped on AP. Also, if any of you guys in the states need a couple pm me. I hope to end up with about 150 fish to grow out.

BTW, this system was designed to grow out fish in monthly stages, but I want to get a rush start this year. Normally there would not be more than 80 pounds of fish in the system, in 12 happa nets at 12 different stages of growth; allowing for 360 fish to be harvested per year.

jazzplayermark, I will get some food coloring and try it. Its heck to catch tilapia in a 300 gallon tank so the closer to correct I am the better!

What I want to end up with is perhaps only 2 male hornorum and 3 to 6 female mossambica's. Thats what Im hoping for anyway.. The Hornorum as so much more tame and are a large fish too, so I might just go for all hornorum. At this point though I hape I have any females..

Are there any good books with info for raising Tilapia? The info here is fabulous, but I can't be online all the time.

We will be looking for tilapia mossambica fingerlings or breeders in a few weeks.