Can I throttle down a Little Giant pump?

[steevareno]

I have two 4-MDQX-SC as returns on my 180 and it is too much flow passing through my sump/fuge(75 gallon). I have a ball valve on each return and wasn't sure if i can slow them down. They are external magnetic drive pumps rated at 1225gph@ 3Ft. of head pressure. Will this shorten the life of the pump? TIA

 

[smcnally]

Yes you can throttle down the output of the pump. I don't believe it shortens the life of them pump, but I could be wrong on that part.

 

[Cheetos]

I thought Mag pumps were the only ones you could throttle down.

 

[smcnally]

I thought Mag pumps were the only ones you could throttle down.

That is a Mag drive pump.

 

[Scuba_Dave]

You can throttle down any pump. The deciding point should be will it harm the pump (back pressure) & shorten the life.
AND, am I wasting a lot of electricitywith the bigger pump?

 

[NateHanson]

You can throttle down any centrifugal pump (all our flow pumps are centrifugal pumps), and in some cases the higher head pressure will actually REDUCE the energy consumption of the pump!

Nate

 

[Chris L]

i have a little giant three that i had to throttle down and it seems to be running with no problems

 

[ReeferMedic]

Why not tee it off and let some go back into your sump? That way, you aren't putting any stress on the pump at all.

 

[NeO]

Why not tee it off and let some go back into your sump? That way, you aren't putting any stress on the pump at all.

Yep, but he still getting to much flow in his sump!!
I would just take one of the pumps off line, and T off the return.

Gustavo

 

[steevareno]

What's the ideal turnover rate for a reef? When i first started out 9 years ago, the rule of thumb was 10X. I have just one plugged in now and the flow seems too slow. Any good external pumps around 600GPH?

 

[steevareno]

bumpareeno...

 

[NeO]

The turnover should be well over 10x inside of the tank, that doesnt mean that you should have 10x going into your sump.

 

[steevareno]

So, less than 10X into the sump? The higher flow gave me some nasty microbubbles everywhere.

 

[steevareno]

What flow rate is ideal? I have one pump running and it seems to slow(1200gph on a 180). Was thinking of adding a submersible with about 600gph.

 

[NeO]

I would stay into the 600 to 1000 galons range, and add some extra flow with Powerheads, closeloop or tunzes.

 

[steevareno]

Curious as to why so slow? I do have Tunze/Seio powerheads to add though. Also have an oceansmotion 4-way on the first return and was think of adding penductors to the corner returns. Thanks

 

[denvig]

The main use for a sump is a place for our skimmers, heaters and possibly a fuge. None of these need a flow of more than 600 gph. In fact even this is probably much to fast for a skimmer to work efficiently. If you really think about it, at any given time all we are trying to send to the skimmer is a paper-thin layer of water at the surface of out tanks. This is the part of the water that has all the organics and proteins that we are trying to skim out. In a 180 gal tank this amounts to less than a cup of water so why are we trying to send it flying past our skimmers at lighting speed? Yes you need a 10 or more times flow rate IN the tank but NOT through the sump. As Gustarvo points out use power heads, Tunze or closed loops for this.

 

[steevareno]

I understand that i need high flow in the tank and not the sump. Hey, I can save money on electricity!

 

[denvig]

Hey, I can save money on electricity!

Now you?re getting my point

 

[JD46]

Steve,

I plan to use a blueline BL-800 (NS series) for the return on my 180. This is a pretty efficient external pump and should provide more than enough flow through the sump for my equipment. Plus, it will use a lot less power than the Little Giant or comparable external pump.

Here is the product link

http://www.bluelineaquatics.com/products/water_pump/ns.html

JD