Matching MegaFlow to Return Pump

[dylanjs]

Hi Reefers,
I need a little translation:

This appears on the AGA website:
Aquariums up to 110 gallons are fitted with one MegaFlow? Overflow and are rated for a maximum flow through of 600 G.P.H. (Using a rated 2,400 G.P.H. pump at a 5 foot head).

If it's rated for 600GPH, why would someone use a 2400GPH return pump? Sorry for being thick, but I don't get it. :scratchch

I have a Gen-X [FONT=Verdana, Arial, Helvetica]PCX-30 rated at 825GPH. Is this not strong enough?

Thanks![/FONT]

 

[masterswimmer]

Dylan, any pump rating is at zero feet of head pressure. So the ratings from pump manufacturers is misleading.

You need to calculate the amount of head loss and then the associated GPH needs to be accomodated by the overflow.

Each 1' of height the pump has to push the water up, translates into lost GPH. Each 90 degree elbow=1' headloss. The friction inside your pipe=headloss. Ball valves, unions, check valves, etc = headloss.

It's very easy to conceive how a 2400 gph pump can be used on a 600 gph overflow. You just have to be precise in your headloss calculation.

HTH,
Russ

 

[nyumpa]

go to reefcentral.com, they have calculator(s) on the left on the page
for various things......plug in the info and get your answer

hope this helps

 

[dylanjs]

Russ, you always have the answers!

How much is lost per foot of height? What about curves that aren't 90 degrees? How do you calculate for loss due to a chiller (the pipes are coiled)?

 

[dylanjs]

The calculator on ReefCentral is great, but they don't have my pump listed...

 

[masterswimmer]

Russ, you always have the answers!

How much is lost per foot of height? What about curves that aren't 90 degrees? How do you calculate for loss due to a chiller (the pipes are coiled)?

LOL, not always, but thank you for the kind words.


Curves are a source of head pressure also (less than a stiff 90). A chiller creates loss, so does a calcium reactor, every single source of friction or restriction creates loss.

There is no 'across the board' answer to how much is lost per foot. It depends on the pump you're using. They all vary. I'll see if I can locate a chart for the Gen-X [FONT=Verdana, Arial, Helvetica]PCX-30.

R
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