Water Flow - Overflow Box/Skimmer/Return Pump - All Equal GPH?

[dasher]

Hello All -

Okay, this newbie to SW has racked his brains and Google-searched until he's completely confused! Please answer these two questions for me (after all the details are given):

I am setting up a 75 gallon tank with a 20 gallon sump/refugium. My HOB overflow box is the eShopps PF-300. The protein skimmer is the AquaC ev-180. AquaC recommends the Mag 7 pump for this skimmer. The skimmer will not be in the sump. The skimmer has a flow-through rate of 275 gph.

My questions, please:

If my overflow box is rated at 300 gph and the Mag 7 pumps at ~475 gph at about 3' should I be getting a Mag 9.5 for the skimmer and leaving the Mag 7 to serve as the return pump? Will this arrangement be safe to both the tank and the sump water levels?


Many thanks for any and all answers! I'm having a bit of trouble getting my head around the idea of "X amount of water going out and Y amount of water coming back".

Dan

 

[snowmansnow]

Ok .
1- whatever return pump you get make SURE the flow is NOT greater than your overflow box can handle otherwise it will fill up and overflow.

That being said use whatever the company recommends for the hang on skimmer. It won't affect your water level.

X amount of water going to the sump is whatever the return pump in the sump is pumping.

If you have any more questions you're free to message me. I'm sure others will chime in too.

B


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[russ-iv]

never heard of an overflow box getting filled faster.
usually the return is .5 larger to the sump than the xfer to the DT.

i have a 6,250 gph pump on standard 1" lines. my t's would pop off before i filled it faster than it could drain.

to answer your question. flow is usualy the net of powerheads and return pump's gph. turn over is the rate you turn the entire tank over and is determined by return pump/pumps.

....ime

 

[snowmansnow]

I must have misunderstood the question. I thought he was considering putting the 9.5 in the sump... Which would be more than the overflow is rated for


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[russ-iv]

SnowManSnow;1054705 wrote: I must have misunderstood the question. I thought he was considering putting the 9.5 in the sump... Which would be more than the overflow is rated for


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sorry i must have misread. mag 9.5 at 3' is 730+ gph. if you have 2 returns at 300 gph then that is 600 gph minus the 45 y adapter to reduce it more.

if it is a single return then i would go with a different pump.

hope that clarifies.

 

[dasher]

SnowManSnow;1054705 wrote: I must have misunderstood the question. I thought he was considering putting the 9.5 in the sump... Which would be more than the overflow is rated for


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You are correct. I thought that since AquaC preferred the mag 7 and I have to position my skimmer outside the sump, that with the distance involved my skimmer would be better served with a mag 9.5 pumping from the sump to the skimmer.

Thank you and Russ for your replies - I failed to word my question properly.

Let me see if this works:

Does anyone see any trouble with this arrangement:

300 gph overflow box - mag 9.5 feeding a aquaC ev-180 - mag 7 feeding back to the main tank.

Do these 4 pieces of equipment seem "balanced" with each other? I have the feeling I need more capacity in the overflow box area relative to the two pumps and skimmer and what they can move.

Thanks again!

D.

 

[dasher]

Russ-IV;1054711 wrote: sorry i must have misread. mag 9.5 at 3' is 730+ gph. if you have 2 returns at 300 gph then that is 600 gph minus the 45 y adapter to reduce it more.

if it is a single return then i would go with a different pump.

hope that clarifies.

LOL!

I'm trying, I promise I'm trying! If I were to tee off the mag 9.5 from the drain to the refugium and the skimmer, obviously with more of the flow going to the skimmer, then that would tune down the gph rate and keep everything more balanced regarding filling the sump vs the 75 gallon tank and neither would overfill. I mean if AquaC recommends the mag 7 yet the ev-180 only has a flow through rate of 275 gph, a tuned-down 9.5 will certainly be adequate for the compensated mag 7 (considering the distance involved in moving the water to the skimmer). The mag 7 could then be used as the return pump with the 2' - 3' distance being another pump "buffer".

I'm confusing myself now...

D.

Sound about right?

Dan

 

[russ-iv]

dasher;1054720 wrote: LOL!

I'm trying, I promise I'm trying! If I were to tee off the mag 9.5 from the drain to the refugium and the skimmer, obviously with more of the flow going to the skimmer, then that would tune down the gph rate and keep everything more balanced regarding filling the sump vs the 75 gallon tank and neither would overfill. I mean if AquaC recommends the mag 7 yet the ev-180 only has a flow through rate of 275 gph, a tuned-down 9.5 will certainly be adequate for the compensated mag 7 (considering the distance involved in moving the water to the skimmer). The mag 7 could then be used as the return pump with the 2' - 3' distance being another pump "buffer".

I'm confusing myself now...

D.

Sound about right?

Dan

lol you're killing me. do you have 2 or 1 overflow box?

if it is 1 tone it down to 4-500 gph. otherwise your fine with the mag 9.5.

skimmer rating doesnt matter. water is homogenous.

i wont get in to it but that is my experience.

 

[dasher]

1 overflow box. Sorry, tone what down to 4-500 gph? The return pump or the skimmer pump?

My best regards Russ, thanks so much.

Dan

 

[russ-iv]

dasher;1054735 wrote: 1 overflow box. Sorry, tone what down to 4-500 gph? The return pump or the skimmer pump?

My best regards Russ, thanks so much.

Dan

the return.

skimmer doesnt matter. crank that baby to 5 billion gph or 100. itll still do what it does.

 

[dasher]

Russ-IV;1054740 wrote: the return.

skimmer doesnt matter. crank that baby to 5 billion gph or 100. itll still do what it does.

Excellent - thanks so much!!!!!!!!!!!


D.

 

[mufret]

According to eShopps, the PF-300 has a 1" bulkhead. The size of the bulkhead will determine the maximum amount of water the overflow can handle. That being said, a 1" bulkhead can handle approximately 600 - 700 gph so you should select a return pump that will not exceed that rating. There's no reason that you need to run the overflow at it's maximum, however. As far as the skimmer is concerned, you'll run into a similar situation. The EV180 also uses a 1" bulkhead for the drain so if you plan on running a Mag 9.5, which pushes a max of 950 gph, you'll want to add a gate or ball valve in-line so you can control the amount of water going to the skimmer so you don't exceed the 600 gph or so that the 1" bulkhead limits the skimmer to. Assuming you already have the pumps (Mag 7 and Mag 9.5), you will need to do the same if you plan to use the Mag 9.5 as your return pump.

 

[dasher]

mufret;1054747 wrote: According to eShopps, the PF-300 has a 1" bulkhead. The size of the bulkhead will determine the maximum amount of water the overflow can handle. That being said, a 1" bulkhead can handle approximately 600 - 700 gph so you should select a return pump that will not exceed that rating. There's no reason that you need to run the overflow at it's maximum, however. As far as the skimmer is concerned, you'll run into a similar situation. The EV180 also uses a 1" bulkhead for the drain so if you plan on running a Mag 9.5, which pushes a max of 950 gph, you'll want to add a gate or ball valve in-line so you can control the amount of water going to the skimmer so you don't exceed the 600 gph or so that the 1" bulkhead limits the skimmer to. Assuming you already have the pumps (Mag 7 and Mag 9.5), you will need to do the same if you plan to use the Mag 9.5 as your return pump.

As of right now I have 2 mag 7 pumps. I'd like to avoid buying a mag 9.5 or an AquaC ev-120, darn protein skimmers are expensive! Doing fresh water tanks sure did spoil me!

Thank you for your reply.

Dan

 

[mufret]

If you have 2 mag 7's, you're set. Use one for the skimmer,which is what the manufacturer recommends, and the second as your return pump.