how many GPH for return pump - NEW question please read post #39

ok, the light bulb went on! FINALLY!!! thx so much for the article AZ. Actually seeing his visual display with water flow through helped tremendously. Now, I guess I need to figure out what my overflow rating will be.

 

Does the tank have a built in overflow box or do you currently own a hang on back overflow box?
If not, there are some good inexpensive HOB choices like Eshopps and Lifereef of places like Glass Cages make kits where you can drill the tank(if it is not tempered glass) and install an internal overflow.

 

you definitely need to drill baby drill if that tank don't have water in it OFK!

 

oh I know the drill baby drill I think that would be a rather hilarious video if I ever attempted that. AZ, it is a pre-drilled tank with an overflow built in left hand rear corner.

 

I only use the return pumps for flow,and have 2 700GPH pumps in the sump. It's likely about 1,000GPH once the head is factored in. I thought my setup was less than what most people have for reefs, but if the overflow is just in one corner it probably can't take as much as my 18" one, but that would also depend on the height of the slots.

 

What size bulkhead is in the overflow box? That and the linear inches of overflow weir measured across the top will determine the safe overflow rate. By that I mean if the box measures 6"x6" and you have 12" of combined overflow area versus say the box is 9"x 9" for 18" of overflow weir etc. The more the better in most cases. My overflow is a center style so is three sides of 6" each for 18" of surface area as an example and I flow about 900 GPH through a 1" Stockman standpipe with a WaterBlaster HY-5000 return pump at about 4 feet of head.



If you know the manufacturer of the tank they should publish their overflow rating.

 

where can I find that information published? I went to the company's website - it's deep blue professional and couldn't find that information. Maybe send them an email? I would think it would be on their website but it's not.

 

I'll bet someone here can help with that info. If not an email to them would probably get it too.

 

That is a really inefficient way to get flow. Which means it wastes more power and adds more heat than you need to. You are paying a big penalty in an open system.

 

Everything AZ says is correct... but 3-5x tank volume is low compared to what some do. It's all I do, but my point is that if you have a pre drilled tank, there is no way the overflow in it is not going to handle 200-350 gph.

If you do need to know, then like AZ has said, you can calculate it and figure it out... but I will bet money you can easily do 350 gph.