Except the opening for the discharge in an IBC is at an odd angle and is not pipe size. The opening is somewhere between 1-1/4 and 1-3/8ths. That IBC lower drain is a strange size. The valve is a size I am not familiar with.
Also are you sure that small fingerlings cannot fit through those squares? I know I could not use that trap for my fry tanks.
Biggest problem I have with trying to use the drain and valve on an IBC when used as a fish tank is, How the heck do you clean the screen when it is in the bottom of a full tank?
I like using a SLO type drain where I can actually pull the whole pipe up and clean the screen at the bottom without having to go head first into the water. If you are dealing small fry, you will probably need something more like a sponge that you will have to clean or swap daily. If they are fingerlings, then a net pot can be used on a pipe for a grate like a SLO drain.
How I do it is I raise the fry to fingerlings and move them to the grow tank. That leaves the IBC empty of critters. I then close the outflow and inflow valves, taking the IBC off the line. I then pump out the IBC with a portable 1/4 HP submersible pump into my catfish pond. I remove and clean the screen and clean the IBC with a baking soda wash. I then pump that solution in to the catfish pond. I then spray rise the tank with clear water and pump it into the pond.
I then refill the IBC with captured rainwater, salt it to 1 ppt, and mechanically aerate it for 24 hours. I then toss in some ''canary gold fish.'' If they live for about 2 or 3 days, I bring the IBC back on line. And do the fry thing again. But I always empty and clean the screen and tank between fry crops.
But Phil, what happens if the screen gets clogged up when you are not yet ready to move the fingerlings to the grow out tank?
I've learned the hard way to keep anything that might need regular cleaning (or even not so regular cleaning) accessible at a moment's notice. When a tank starts overflowing due to a clogged drain does not always align with when you plan on moving fish.
(of course an indoor system may have less issues with leaves and debris getting in but strange things can still happen.)
Checking flows is part of daily tasks here and I like the cleaning as needed to be easy since if it isn't, it might not always get done when needed and that can cause real problems.
The IBC lower drains, as seen from the inside of the tank is an irregular size from one tote to the next. This is because of the way they are made. I have found some IBC's with a removeable drain valve an some with the valve molded in.
So i can see the need to wrap pipe tape around the screen to get a tight fit.
Phil, If you tap a 1/4" hole in the pipe, near the screen then you could use air to blast back through the screen to clear anything clogging it. (just a thought)
Great idea Tony.
Thanks, let me know how it works for ya
TCLynx is right about clogging. We had to break out every other bar in the strainer and drill 3-5/16ths holes in the solid ends. Good point TCLynx. Forgot to mention that, hehe.
I would say make sure you have a brush or tool that will work for cleaning the strainers without requiring going head first under water into an IBC tank (that could be quite dangerous actually.)
I would not mind sending my former wife in head first .... ''I don't know officer, I came out to the grow house this AM and there she was with only lower legs and Ruby Red Slippers showing. Is she a goner?"
But the long handle brush is a good idea. But since this discussion, I think the better idea is to open up the strainer even more and use larger fish in the IBC.
No matter how wide open you make a grate, you still have to leave your self some way to clean it. What if a big leaf falls in the tank? Or some one leaves a towel hanging on the edge and it falls down in and blocks the drain? That's why I like the SLO drains with a T at the top inside the tank since if one of those crazy things happens (and crazy things do happen somtimes, I know) you still have an overflow.