I installed a 960 gph Laguna power jet pump, and got rid of 3 submersible sponge filters in my 600 gal tank. I stuffed the one inch flex on the power jet pump into the inch and a half flex going to my 2000 gallon external pump and Ultima 2000 filter. I also had to put one of my albino plecos in the 600 gallon tank to control the string algae. I left one Beckett 400 gph double sponge type submersible filter to feed my planter.
Just a little warning, the generic replacement sponge for the Beckett submersible sponge filters are inferior to the Beckett original replacement sponge. I tried both types, the generic type is softer and is the culprit that killed a few of my bigger frys. It doesn't hold up and keep its form like the original Beckett sponge replacement.
The frys don't get sucked into the 960 gph Laguna Power Jet pump case, the holes of the case is small enough to handle one month old fry as I remembered correctly. I have been emphasizing the Laguna Power Jet pump because they sell another type called Laguna Max Flow pump. The case holes on the Max Flow is much larger, it is not suitable for one month old fry.
I turned the 45 degree coupling on the return, so the current will spin around the tank. Hopefully, the poop will settle in the middle and get sucked into the ultima 2000 filter. The picture shows the coupling facing in, it has been turned. When the fry are three month old, I will take out the Beckett sponge filter and Laguna Power Jet filter pumps, and just run my original ultima filter set up which is designed to feed the planter and created a circular current in the tank.
I saw one high quality clear white round Tancho Kohaku fry, I hope it matures with out any blemishes.