what are u using it for? a 10 gallon display? how will you be getting the watter down to the sump? any syphen unit will take p too much room and 600g per hour with a 1in drain will be waaay too much flow thru your tank let alone a sump of only 5-6 gallons..
also another deign ive seen on picos is to drill the bottom of the tank and have a 1 inc pipe come to the surface and a small return pump and it allows the surface to skim and overflow into a 1" pvc tube
Hey I have a 10g ready to go for a sump...I've also drilled afew small tanks 5.5,10,20l... if your drilling plan for it to take afew tanks it is very difficult ...also some brands are tempered. You may also concider building an acrylic tank.it wouldn't be that expensive for that size