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View Full Version : Cannibalistic tilapia; Solution: Home made sorter



Riverside
06-12-2010, 07:20 PM
my tilapia have been spawning for the past four months, so I'm very much into the learing curve; I've placed the fry into a 10 gallon tank, but one of the problems has been as time passes the older fry get bigger and the new fry get eaten!

My wife has done a yeoman's job of trying to net out the hungry "monster fry" but not a good solution; I tried googling "small fish graders" or "small fish sorters" and all I found were massive machines costing hundreds if not thousands of dollars.

Solution: make my own! :D The prototype is made from acrylic and 304 stainless steel tubing, and it works very well sorting the perpetual hungry from the innocents <g>[attachment=0:4pzwnjy2]100_2539.jpg[/attachment:4pzwnjy2]
[attachment=1:4pzwnjy2]100_2541.jpg[/attachment:4pzwnjy2]

stucco
06-12-2010, 08:15 PM
Thanks for posting that. I hope to see it in action.

JCO
06-13-2010, 05:38 AM
Wouldn't it have been just as easy and maybe even less expensive to go on http://craigslist.com and buy a few more 10 gal tanks...they are quite cheap on there here in Fla. Just a thought. Cannibalism is common place among most fry especially among cichlids (Talipia) and Koi. :mrgreen:

Riverside
06-13-2010, 05:58 AM
Wouldn't it have been just as easy and maybe even less expensive to go on http://craigslist.com and buy a few more 10 gal tanks...they are quite cheap on there here in Fla. :mrgreen:
Space is a problem for me, I just don't have the room for more tanks (at least inside, once the greenhouse is finished that may solve that problem); but even in one group of fry they grow at different rates, and the bigger ones do go after their slower growing brothers;

The cost of the materials is small, so it's not really the money (the labor, however, is another thing! :D)


Thanks for posting that. I hope to see it in action.
Thanks stucco, this is just a prototype, I've tested it out and it works fine, but further refinement is needed. As soon as the rough edges get worked out I'll post a pic of it in action.

davidstcldfl
06-13-2010, 06:14 AM
Cool....stainless steel tube....break out the orbital welder... :D

I remember having a plastic 'birhting' box years ago, when I was raisng sword tails. It had a plastic 'V' in it...the bottom of the 'V', was an open slot.
The idea was the mother was above the 'V'...and the fry went down through the slot, into the lower 1/2 of the box.

Might be a way to do something like that too.


I just went over and looked at the 10 gal I have with hundreds of fry. Man, have they grown ! I better get the other 10 gal set up fast.
I also, now have 4- 55 gal barrels that were used as holding tanks for fry. I better get them set up too !

JCO
06-13-2010, 06:42 AM
I know you really don't want to lose any fry but it's natural elimination...survival of the fittest...in this case...survival of the fastest growing which when you think about it, that's a good thing...eliminate the slow growers and soon your strain will be stronger for it. :mrgreen:

francois
06-13-2010, 07:37 AM
hi all

i agree with survival of the fittest
i grow my fry in a smaller dam and keeping in age groups
later sorting the bigger/faster growing males
and releasing them into my system
selling smaller fe/males

francois
06-13-2010, 07:43 AM
this is just a prototype, I've tested it out and it works fine
nice i will do something symm.

Riverside
06-14-2010, 08:03 PM
I know you really don't want to lose any fry but it's natural elimination...survival of the fittest...in this case...survival of the fastest growing which when you think about it, that's a good thing...eliminate the slow growers and soon your strain will be stronger for it. :mrgreen:
I'll never argue with Darwinism, but I think you're misunderstanding my situation. Since I only have one fry tank, the fry from a hatch two weeks ago are in the same tank with newly released fry. The newly released fry may be genetically superior to the hatch from two weeks ago, but will get eaten by possibly genetically inferior but much larger fry. Hence, the need for a sorter. Darwin's law can't work if a new generation is eliminated just because they are smaller than the existing examples of the species. Natural selection doesn't work like that.

jackalope
06-14-2010, 09:27 PM
I just go to the thrift store and buy all of the old plastic aquarium plants they have ..... they practically give them away, because they are such a nuisance to them ..... then after I wash them thoroughly, I throw them into the tank and let nature take it's course .... some of the plastic plants will float to the top, some sink to the bottom, and some end up in the middle ;) If the get eaten with all that plastic to hide in, they deserve it! This has worked with Guppies, Swords, Mollies, Platties, Tilapia, and Cichlids among others!

JCO
06-15-2010, 04:54 AM
You are right about Darwin...I knew him...he lived down the street from me....he was always spouting off stuff no one understood or agreed with. We even went to different schools together only his school had teachers and books and I didn't pay attention as now.

Sorry about the mix up on the new and old hatch....but there has to be a space somewhere that you can set at least a 5 gal tank or something to give the new hatch a chance :mrgreen:

badflash
06-15-2010, 05:40 AM
Go with 10 gallon tanks. They are just $10 each new. I drill them and plumb to a common sump and use platic screenwire for the overflow to keep them in. Each hatch goes into a separate tank. When you run out of tanks, you have all the fish you need. Once a fish is over 2" it can hold its own, so you can re-mix them.


The advantage of keep them apart and from the same hatch is you can select for the fastest growing fish.

Riverside
06-15-2010, 06:30 AM
Go with 10 gallon tanks. They are just $10 each new. I drill them and plumb to a common sump and use platic screenwire for the overflow to keep them in. Each hatch goes into a separate tank. When you run out of tanks, you have all the fish you need. Once a fish is over 2" it can hold its own, so you can re-mix them.

The advantage of keep them apart and from the same hatch is you can select for the fastest growing fish.

That would be great but I'm space-challenged :D


....but there has to be a space somewhere that you can set at least a 5 gal tank or something to give the new hatch a chance :mrgreen:

I promised the (new) wife I'd keep all the fishies in one room- my back office. There has to be room......hmmmmnnn

[attachment=0:35101czm]100_2542.jpg[/attachment:35101czm]

Just moved all the tanks last week, haven't had a chance to neaten things up, but until I go vertical, that's all the space I have! :D

badflash
06-15-2010, 09:45 AM
Go verticle! There is lots of room! The fry tanks can go above the big tank and share common filtration. Pump up & gravity drain back.

jackalope
06-15-2010, 09:48 AM
Look at all that wall space :!: :lol: :lol: :lol:

Riverside
10-20-2010, 09:17 PM
Hmmmnnn. . . . go vertical- OK Badflash, ! I did <g>;
big breeder tank and tank top left share filtration, other tanks added as biofilter matures:
Phil Spector had his "Wall of Sound", I've got my "Wall of Fish"! :D
(now that I've got the fishies figured out, construction of the greenhouse to hold the aquaponics system should start next month I hope)
Breeder tank, left center; young adult, top left; fry tank, top center, teen/fingerling tank, far right, pre-teen tank (mesh tank inside teen tank)
275 tilapia in 126 cu. ft.! Funny thing is this setup actually works well for me.

davidstcldfl
10-21-2010, 03:58 AM
:D .....nice.

urbanfarmer
10-21-2010, 12:19 PM
Wow, nice! They use this same concept to sort the market-size fish out of ponds.