Overflow question....

[nickthapainter]

I just picked up a 180 gallon RR tank. I was quite surprised to see that it only has 1 overflow.

I am curious as to what is the maximum volume of water that will flow through so I can size up a new return pump.

I'm thinking of a Mag12 but am not sure if this size pump will be too powerful.

Will the this combo pump/overflow work?

TIA

nick

 

[RLG2182]

Is the overflow chamber in the center? How many drainage lines does it have? Diameter hole? If it's Acrylic, you can always drill another drainage hole and do a dual durso standpipe assembly to maximize overflow rate.

 

[nickthapainter]

The overflow is the right corner. The drainage line is 1 inch diameter.

Adding another internal overflow would require draining the tank (like to avoid if possible).

 

[loganj]

I'm gonna go out on a limb and say it's good for about 650-700gph. Is there room in the existing overflow to open the drain hole up to 1 1/2"? That would give you more capacity. Or, again, if there's room, you might drill another 1" hole in the existing overflow and put in another standpipe. If you leave it as is, and go with the Mag 12, I'd put a valve on the pressure side of the pump so you can choke it back a little if it's too much. That won't hurt the pump and it's convenient if you have to remove the pump. Beware of running it at max capacity if you have a sponge prefilter. If the sponge starts to clog, you could run the tank over.

 

[nickthapainter]

Thanks for the help!

Will go for a mag12 with the option of throttling it down.

I had to remove the prefilter (was already gunked up)

There are bioballs in the overflow chamber (no pipes whatso-ever).

I want to remove the bioballs (worried about nitrate buildup) but am worried that noise will then become a factor.

 

[loganj]

You could ditch the bio balls and install a Durso type standpipe. They are pretty quiet and flow well.