210g tank 84'x24'x24'

[pmrossetti]

OK folks, What submersible pump do I use as a return? I guess I'm looking at about 700-1000g ph. Thanks everyone at RC. You're the best. Only use sub pumps. Had too many friends have disasterous leaks with externals. Stand 36". So about about 5' to tank top.

[reeferx2]

I had a Mag18 on my 125g and have upgraded to a 280 and am still using it. It should give you around 1000gph after your head loss.

[sjm817]

An Eheim 1262 could probably just squeak out around 700 GPH.

[jayb12]

ive got a 250 with a 84x24x28 and im using a mag 18. the more flow the better!

[pmrossetti]

Using power heads for flow. Just want 3-5 x volume for return.
Thanks

[jayb12]

awww, im using no power heads, its looks so much cleaner that way!!

[nikon187]

you don't want all your flow from your return pump alone. It will cause micro bubbles that don't have time to disipate because of the high rate of flow through the sump. 5-10X turnover through your sump, 20-40X turnover in the display. If not using powerheads a closed loop may be in order.

[pmrossetti]

Thanks nikon187, but closed loop is out. Too much chance for leaks. I think 3-5x thru sump is enough.

[wetWolger]

if your careful, a CL is extremely safe

[jayb12]

<a href=showthread.php?s=&postid=15566355#post15566355 target=_blank>Originally posted</a> by nikon187
you don't want all your flow from your return pump alone. It will cause micro bubbles that don't have time to disipate because of the high rate of flow through the sump. 5-10X turnover through your sump, 20-40X turnover in the display. If not using powerheads a closed loop may be in order.

not true at all. i have no powerheads and a mag 18 for return i have zero micro bubbles.

i split the return line into 2 to tips on either end of the tank and theres no problem.