building a sump for a non ReefReady tank

[PiscesLou]

I purchased a 90 aga tank about 2 months ago, I should have paid a few more $$$ for a reef ready model...but I didnt so here I am. I have a 50 acrylic tank that Im converting into a sump. I have a general idea of what the actual sump will look like the part that I need help is the overflow. does anyone use the CPR HOB overflow. Does it work pretty good? anyone have a DYI overflow that does not require drilling a hole on the main tank? any suggestions would help. TIA

 

[PiscesLou]

anyone know of a link or thread that explains how a j tube style overflow works?

 

[fishfreek]

CPR overflows are not exactly classified as J tube tyles but more or less a C shell style. This is because the chamber that water passes up and over the lip of the tank runs the entire lenght of the overflow vs a U tube or J tube style that has independant 1" tubes.

Water enters one side of the oveflow (the side in the tank) and via syphon action goes up and over the tank side to a second chamber. This chamber has a wall that is often only 1/2 the height of the chamber's other 3 walls. Water then cascades over this shorter wall into another chamber that has a drain fitting that allows the water to drain into the sump.

Since water will naturally try to equilize its level the outside chamber is usually little lower in water level than the main tank. If the U tube remains free of air water will flow up and over the side to try to rase the outside chambers water level but since the shorter wall never allows the water levels to equlize then the overflow runs consistantly untail the pump putting water into the tank stops.

I would check out the DIY forum here for info on how to build your own overflow. You can also check out http://www.lifereef.com for quality U tube overflows.

 

[RMPD109]

Check the attached link. It is general info on sumps but I am including it for the animated illustration. It shows how an overflow box performs. I hope it helps.

http://www.melevsreef.com/what_sump.html

 

[tinman]

I did one for a non drilled tank but it looks drilled. The plans are here

http://www.guarriello.net/overflow.htm

works very well if you follow the design it will not loose suction. I drained the tank and it didn't loose suction.

I have pics in this thread.

http://www.aquariumadvice.com/viewtopic.php?t=47779

edit

 

[PiscesLou]

Thanks everyone for the replies. I have general understading now of how an overflow works , now comes the hard part. will be buying parts tommorow