How to size a pump?

[street fish]

Hello MRs,

I have an acrlyic tank that is 71"X20.5"X36". The tank has two corner overflows with both return and output holes of 1.75".

I am looking to order a pump, and I understand this should traditionally be 5-10 times the tank volume...but given the output/drain holes are 1.75", is there a way to estimate the size of pump needed?

Any help is much appreciated!

Also, please see my other thread - "FREE BEER!"

http://www.manhattanreefs.com/forum/general-discussion/78194-mr-please-help-set-up-free-beer.html

Looking for people to help with setup!!

Thanks all

 

[street fish]

Also, I think I will be constructing a sump out of a 55 gal tank

 

[albano]

...but given the output/drain holes are 1.75"..

If you're saying that the ACTUAL hole, without the bulkhead is 1.75, then you'll only be able to have a 3/4" OR 1" bulkhead/tubing...check here to see amount of flow that you can have... http://www.flexpvc.com/WaterFlowBasedOnPipeSize.shtml
since it's acrylic, you may want to consider drilling larger holes... what's wrong with sump in pic?



.

 

[stage3-S4]

also are you doing a remote sump, or will it be under the tank? If it is remote make sure you calculate the distance from the sump to the tank. You would want to use a head rated pump in this case, such as an iwaki.

 

[chuck116]

Remember that you can also use powerheads, < mp 40 > for flow in tank. but remember that more powerheads mean more heat. Mp 40 little or no heat the motor is outside the tank, also take into consideration noise from your overflows. The more you flow the louder it is . IMO. Also bigger pump more electricity. I think reeflo pumps use less electricity. look on reef central there is a flow calculator . If im not mistaken you can only flow 600 to 700 gph from a 1 inch hole. I agree if its acrylic you may want a bigger hole , but I dont know much about that or which size.

Good Luck Chuck & Anna Maria

 

[street fish]

If you're saying that the ACTUAL hole, without the bulkhead is 1.75, then you'll only be able to have a 3/4" OR 1" bulkhead/tubing...check here to see amount of flow that you can have... http://www.flexpvc.com/WaterFlowBasedOnPipeSize.shtml
since it's acrylic, you may want to consider drilling larger holes... what's wrong with sump in pic?



.

Thanks Albano. Yes, the actual hole is 1.75", I recently found out I will be using 1" bulkheads.

As for the sump in the picture, it is a wet/dry with the following dimensions - 24" long x 24" high x 12" wide.

Too small right?

Thanks for your help Albano

 

[street fish]

also are you doing a remote sump, or will it be under the tank? If it is remote make sure you calculate the distance from the sump to the tank. You would want to use a head rated pump in this case, such as an iwaki.

It will be an under tank sump. As for head rated, what does that mean exactly?

Also, I am thinking a blueline 55. What do you guys think with this choice? Any experience with noise?

 

[street fish]

Remember that you can also use powerheads, < mp 40 > for flow in tank. but remember that more powerheads mean more heat. Mp 40 little or no heat the motor is outside the tank, also take into consideration noise from your overflows. The more you flow the louder it is . IMO. Also bigger pump more electricity. I think reeflo pumps use less electricity. look on reef central there is a flow calculator . If im not mistaken you can only flow 600 to 700 gph from a 1 inch hole. I agree if its acrylic you may want a bigger hole , but I dont know much about that or which size.

Good Luck Chuck & Anna Maria

Thanks Chuck and Anna Maria! Very helpful. When you say 600-700 gph, is this the size of pump I should be using? Is that inclusive of the fact that there are two returns.

 

[ming]

Since you said there are TWO 1.75" holes in each of the 2 overflows, that means each hole can handle up to 600gph drain. 2 of the 4 holes will probably be returns, so you can handle up to 1200gph. Considering the size of the tank, I would try to use the 1200gph. You can use a stronger pump (such as the reeflo pumps as mentioned) and make a manifold so you can T it off for other uses such as carbon reactor, phosban, chiller, UV, calcium reactor, etc if you ever want to add them. Just make sure to put a valve on each so you can adjust each flow.

 

[street fish]

Since you said there are TWO 1.75" holes in each of the 2 overflows, that means each hole can handle up to 600gph drain. 2 of the 4 holes will probably be returns, so you can handle up to 1200gph. Considering the size of the tank, I would try to use the 1200gph. You can use a stronger pump (such as the reeflo pumps as mentioned) and make a manifold so you can T it off for other uses such as carbon reactor, phosban, chiller, UV, calcium reactor, etc if you ever want to add them. Just make sure to put a valve on each so you can adjust each flow.

Thanks Ming - very informative. I am going to look into reeflo pumps now!

 

[street fish]

So I have done some research and it seems that 1" bulkheads will flow approximated 350 gph. Therefore, since my tank has two outflows, I would assume around 700 gph...

With the additional headloss - I am thinking a pump with around 1000 gph.

The Blueline HD is rated at 1100 gph...

Thoughts? Advice?

 

[masterswimmer]

1" pipe can handle 600 gph, not 350. Therefore, each of your two 1" overflows can handle 600 gph totaling 1200 gph. With headloss you can easily use a pump with a rated flow of 1500 - 1600 gph. Remember, with two returns/overflows each, the headloss is doubled.

Russ

 

[street fish]

1" pipe can handle 600 gph, not 350. Therefore, each of your two 1" overflows can handle 600 gph totaling 1200 gph. With headloss you can easily use a pump with a rated flow of 1500 - 1600 gph. Remember, with two returns/overflows each, the headloss is doubled.

Russ

Many thanks Russ. So Eheim 1262 too little?

 

[ming]

Many thanks Russ. So Eheim 1262 too little?

900GPH pump, pumping up lets estimate 5 feet, will probably pump ~650-700GPH after head pressure. Is that too little for you? its really up to you to decide. We already told you that you can handle UP to 1200GPH with two 1" bulkheads. You can always go less upon your discretion, and if you go more, just throttle it with a ball valve so your tank doesn't overflow. We're giving you the information, you need to make the decision.

 

[motortrendz]

just remeber that 10 times rule aplies to basic flow in a tank some sps tanks have 20-30 times more flow.. and the miggest mistake people make is thinking that the 10 times has to come from the return from the sump.. the sump will only handle a certain volume decided by the bulkheads used for the drains.. russ explained that already. after you figure outh your return flow then you can use hydors, mp40s, a closed loop system to create your flow in your tank.. making sure you dont have any dead spots for detrious to build up..

hope this helps..

 

[street fish]

900GPH pump, pumping up lets estimate 5 feet, will probably pump ~650-700GPH after head pressure. Is that too little for you? its really up to you to decide. We already told you that you can handle UP to 1200GPH with two 1" bulkheads. You can always go less upon your discretion, and if you go more, just throttle it with a ball valve so your tank doesn't overflow. We're giving you the information, you need to make the decision.

It was my understanding that two 1" bulkheads would equate to 700gph being drained from the tank. That is why I am confused as to what "can handle up to 1200gph" means...

Apologies if I am not fully understanding the concept yet, this is my first go with a drilled tank. Always used Eheim canisters in the past.

All your help is much appreciated.

 

[masterswimmer]

1" pipe can handle 600 gph, not 350. Therefore, each of your two 1" overflows can handle 600 gph totaling 1200 gph. With headloss you can easily use a pump with a rated flow of 1500 - 1600 gph. Remember, with two returns/overflows each, the headloss is doubled.

Russ

The red should help.

Russ

 

[street fish]

just remeber that 10 times rule aplies to basic flow in a tank some sps tanks have 20-30 times more flow.. and the miggest mistake people make is thinking that the 10 times has to come from the return from the sump.. the sump will only handle a certain volume decided by the bulkheads used for the drains.. russ explained that already. after you figure outh your return flow then you can use hydors, mp40s, a closed loop system to create your flow in your tank.. making sure you dont have any dead spots for detrious to build up..

hope this helps..

Thanks Motortrendz, this is very helpful.

Sorry guys, this whole time I was under the impression that since my 1" bulkheads would "drain" x amount of water, I thought the return pump needed to match that amount (after headloss). Can someone help clarify, I feel like I am missing something.

Also, can someone direct me to where I can learn what a "manifold" is?

Apologies if these questions are all extremely elementary. I have been trying to read all the sump setup guides, and I have not been able to find this level of detail.

Thanks everyone

 

[ming]

It was my understanding that two 1" bulkheads would equate to 700gph being drained from the tank. That is why I am confused as to what "can handle up to 1200gph" means...

Apologies if I am not fully understanding the concept yet, this is my first go with a drilled tank. Always used Eheim canisters in the past.

All your help is much appreciated.

I'm not sure where you get your calculations that two 1" bulkheads will handle 700gph. Multiple people on this thread has told you each 1" bulkhead will handle 600gph draining and since you will have 2, that means 1200gph

 

[street fish]

The red should help.

Russ

Thank you Russ - you have been extremely helpful.