Gravity flow rates tank to sump?

[fishy929]

I am in the process of upgrading my reef system now that I know what i'm doing :roll: Anyway, I am putting in a 90 gallon acrylic with a 30 gallon berlin sump. I plan on returning water (and providing current) via a Iwaki 1200gph pump. What would be the minimum overflow size to keep up with this much input?

My overflow is 6"x10" trapezoid and will be centered in the tank. I plan on Y splitting the overflow between the two 1" inlets into the sump with flexible piping with no 90's.

I actually found a formula for this. Unfortunataly, the tank will be here before I can crank out an engineering degree

Thanks!

 

[tangir1]

With 1200gal/hr pump, two 1 inch is already pushing it which max aroun 1400 gph (without Y-split). Keep in mind that you want to oversize the overflow since they typically will get clogged to some degree due to tub worms and sponges growning inside the pipe.

So see if you can drill two 1 inch holes, or even better, go with one 1.5 inch or two 1.25 inch.

 

[fishy929]

Thanks Tangirl. So, if I go with two 1.25" overflow holes, I also need to go bigger inlets on my sump right? I would think that reducing the pipe to the 1" inlets would defeat the purpose.

 

[tangir1]

What is the rating on the sump? Or it is a DIYed?

You can always enlarge a drilled hole on the sump, BTW, given that there are enough space for the larger opening.

BTW, it is tangir"1"...

 

[fishy929]

Tangir1,

Sorry about the mistaken identity... I'm not sure what the flow rating is on the sump. In all of my research, I never found any sump with a throughput rating. I thought that was odd, but...

Anyway, my sump is the Euro-fil 240 manufactured by Advanced Aqua Tanks and can be seen on this page The dimensions are 36½ X 13 X 16½. I'm confident that I will have the room to increase the input holes. But again, I'm not sure of the actual flow rate.

I suppose the biggest cramp will to drill the larger holes in the overflow and not be able to return there as well. My acrylic tank does have the black back, so I suppose I could drill 2 or more returns on the backside of the tank. Is that how most people are doing it these days?

 

[tangir1]

When I build a new stand, I plugged the return hole in the overflow box, and use the top of the tank for return. You can also use the back side of your tank if you want, as you mentioned.

Post/search a thread on the DIY forum if you want to know how we plug up a hole, or redrill an opening for larger hole.

 

[fishy929]

Thanks for your help!