Sump pump flow rate

chris k. · May 20, 2018

I am currently using a rio 3100 in my sump for my 110 gallon dt. I am adding a 28 gallon next to dt and plumbing the 28 gallon into my 110 gallon sump. The sump is an eshopps adv 200 i think. Can i split the output on thus pump to 2 different tanks or do i need a bigger pump. Both tanks have enough flow inside the tanks. Just looking for water turnover in both tanks to sump. I only have room for 1 pump in the sump.

Mark Bianco · May 20, 2018

Unfortunately I cannot find a flow chart for this pump. The only information I can find is it 900gph at 0' head and has a max head of 10', this is where it will not pump anymore. If we can guess the flow rate to head height is linear (most are not) and say there is 3' head for each tank (vertical distance from pump to tank output) that's a total of 6' of head pressure. That means you will be losing at least 60% of the flow, or a total of 540 gph. Now subtract that from the 900 gph and that leaves you with 360 gph flow rate. Most tanks have a turnover rate from the sump to the tank ranging from 4 times to 10 times total water volume. I am not even figuring and other restrictions such as vertical distances. Anything is possible, but in this case the math just doesn't add up.

Good luck and happy reefing.

Mark

theMeat · May 20, 2018

That rio 3100 will give you 500gph, if you're lucky, at the around 5 foot of head I'm guessing you have.
That gives you around 4 to 5x display tank water volume going through sump which is perfect for a 110 IMO.
Doesn't leave you any room to tee off and feed another tank from the same pump. As a side if it were me I'd change the rio even if I didn't need a bigger pump. You can get something that is more reliable and generates a lot less heat while supplying a lot more gph.
Would also recommend a separate pump for each tank, unless you have controller or some other means or measuring flow, instead of guesstimating with a tee and valves. You could, if room allows, drill a hole in the sump, with bulkhead, and run an external pump