Corner overflow or a just a tube

[tlaloc]

Hi everyone,
I would like to build a setup of 8 20g tanks all filtered by a central wet/dry filter. I will have those tanks drilled. What would be the best way to do the overflow?

1) With a corner overflow that has a hole in the bottom of the tank and a tube.

2) With just a hole in the top corner of the tank and a 90degree fitting with a strainer on top of it.

3) Hole in the bottom with a tube and strainer but without the corner section

Thank You for your help

 

[RadleyMiller]

I saw this at a LFS, I don't know how to explain it. But drill the back side of the tank at the corner, then run a piece of pipe up to the top and add a strainer where you want it. Then when you want to do a water change, push the piece down so that it is taking in water from a couple inches under the surface (and make sure you sump has an overflow to a drain) then once all of the tank have drained, stand the overflows upright, turn your pump back on, and start filling the sump.


or #2

what is this going to be for?

 

[tlaloc]

Thank You for your quick answer.

I would like to keep some pairs of angelfish and maybe some dwarf gouramis.
I think with the central filtration system it would simplify the maintenance of the filters.

 

[softturtle]

Any of the choices you mentioned would work good. I wouldn't use the corner overflows just becuase they cost a lot and would take up a lot of space in 20 gal tanks. I have a system that is just a pvc pipe that runs through a hole on the bottom of the tank and to the surface of the water. It only cost me around $30 bucks to plumb 6 tanks. I had a bunch of 20 longs that I had drilled in the upper corners. They both work equally well.

 

[tlaloc]

Thank You Softturtle,
on the one drilled on the back of the tank do you use a T fitting outside of the tank for a vent or it is draining fine without one?

 

[softturtle]

I just had those bulkheads that lead out to a 90 degree and I connected soft tubing to that. No T fitting. With this method I would use a bulkhead bigger than is actually needed (or more smaller ones). I had two 3/4" bulkheads (one in each corner) on each 20 gal tank.