Overflow capacity and questions

dbdisok · 03/19/2010, 03:44 PM

I have a 120 gallon 48" x 24" x 24" aquarium with a trapezoid (6" x 9" x 6") center overflow. There are 22 teeth ( 1/4" wide x 1 1/4" long) in the overflow.

I am wondering if there is a formula to calculate the flow my overflow with handle?

This particular overflow came drilled for 2 1" returns. The bottom of the tank is drilled with one 2 1/4" hole and two 1 1/4" holes.

I am looking for input on how to setup this overflow.

Should I run a single drain through the large hole and plumb return flow through the other two holes?

Or, should I used all three hole for drains and plumb the return lines over the back of the tank?

Thank you for any input you might provide.

arrowheadpuffer · 03/19/2010, 05:11 PM

I would use all three drain holes, and do a silent fail safe over flow (search 'herbie' or 'silent fail safe overflow' if you are not familiar) Have the returns come up and over the back of the tank.

Not sure on what flow you can handle, but a single 1" durso/stockman type stand pipe should be able to handle a max of 600gph.

dbdisok · 03/19/2010, 05:15 PM

Thank you for your input.

das75 · 03/19/2010, 08:52 PM

RDO Overflow Capacity Calculator (Excel spreadsheet to download) will give an idea how high the water will be up the slots for different flow rates.

Other option for a drain is use two of the holes for a Herbie drain system and the last for a in tank return rather than going over the top.

dbdisok · 03/21/2010, 09:19 AM

Bump. Looking for more input.

03/19/2010, 03:44 PM	#1
dbdisok Registered Member Join Date: Oct 2008 Location: Moorprak, CA Posts: 270	Overflow capacity and questions I have a 120 gallon 48" x 24" x 24" aquarium with a trapezoid (6" x 9" x 6") center overflow. There are 22 teeth ( 1/4" wide x 1 1/4" long) in the overflow. I am wondering if there is a formula to calculate the flow my overflow with handle? This particular overflow came drilled for 2 1" returns. The bottom of the tank is drilled with one 2 1/4" hole and two 1 1/4" holes. I am looking for input on how to setup this overflow. Should I run a single drain through the large hole and plumb return flow through the other two holes? Or, should I used all three hole for drains and plumb the return lines over the back of the tank? Thank you for any input you might provide. __________________ Present: 55 gallon, LR, LS, HOB skimmer, HOB filter with Chemipure bags, Current Dual Satellite Power Compacts. Established January 2008. Next up 120 gallon RR. Much planning and work to be completed. Current Tank Info: 55 gal reef with sump, L/S L/R

03/19/2010, 05:11 PM	#2
arrowheadpuffer Registered Member Join Date: Oct 2009 Location: CA Posts: 396	I would use all three drain holes, and do a silent fail safe over flow (search 'herbie' or 'silent fail safe overflow' if you are not familiar) Have the returns come up and over the back of the tank. Not sure on what flow you can handle, but a single 1" durso/stockman type stand pipe should be able to handle a max of 600gph. __________________ -arrowhead Current Tank Info: 90g

03/19/2010, 05:15 PM	#3
dbdisok Registered Member Join Date: Oct 2008 Location: Moorprak, CA Posts: 270	Thank you for your input. __________________ Present: 55 gallon, LR, LS, HOB skimmer, HOB filter with Chemipure bags, Current Dual Satellite Power Compacts. Established January 2008. Next up 120 gallon RR. Much planning and work to be completed. Current Tank Info: 55 gal reef with sump, L/S L/R

03/19/2010, 08:52 PM	#4
das75 Registered Member Join Date: Oct 2002 Location: Edmonton AB Posts: 2,269	RDO Overflow Capacity Calculator (Excel spreadsheet to download) will give an idea how high the water will be up the slots for different flow rates. Other option for a drain is use two of the holes for a Herbie drain system and the last for a in tank return rather than going over the top. __________________ . Current Tank Info: 145g Starfire display (mixed reef) w/75g basement sump & 20g refugium, Barracuda return, Dart w/OM 4way CL, AI Hydras and Director.

03/21/2010, 09:19 AM	#5
dbdisok Registered Member Join Date: Oct 2008 Location: Moorprak, CA Posts: 270	Bump. Looking for more input. __________________ Present: 55 gallon, LR, LS, HOB skimmer, HOB filter with Chemipure bags, Current Dual Satellite Power Compacts. Established January 2008. Next up 120 gallon RR. Much planning and work to be completed. Current Tank Info: 55 gal reef with sump, L/S L/R