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Modern-Revolution
02/19/2013, 08:14 PM
So I got this little giant which I plan on running as a return pump up to 3 30 gallon tanks. Mine is model 4-mdq-sc which I now realize is 880 gph and not 1200... would this be strong enough to return and split to 3 tanks about 4 feet above the pump with about 6 feet of plumbing?* Also the outlet is 1/2 inch so should I do all the plumbing at 1/2 inch or should I make it 1 inch?* I'm guessing the gph would be even worse at 1 inch.
This is my first time using external pumps and first shot at pvc hard plumbing.*
Here's a pic of the pump stats and my setup and my plumbing plan.
All criticism appreciated.

http://i7.photobucket.com/albums/y283/BillOne/pump3.png

http://i7.photobucket.com/albums/y283/BillOne/20130216_143511.jpg

http://i7.photobucket.com/albums/y283/BillOne/20130216_143905.jpg

tkeracer619
02/19/2013, 08:51 PM
Yes. Its plenty for a return. In fact its about double the general rule of thumb.

Personally I would return it or sell it and get a much smaller more efficient pump. The 4-mdq-sc will cost you $160 per year. Over a 5 year lifespan you are talking a $500 difference in power cost vs an Ehiem 1260.

Modern-Revolution
02/19/2013, 10:21 PM
Oh, wow.. that's a lot of money that I wasn't even considering. .. didn't realize it used so much energy. The eheim 1260 is one I was thinking of. I just had this external and thought it would be cool. Ty forthat bit. Makes a big difference.

tkeracer619
02/19/2013, 11:52 PM
You're welcome. Sometimes its the hidden costs that get us.

Ron Reefman
02/20/2013, 06:48 AM
Hold on just a second. I'm not sure how anybody can make such a recommendation on pump size with the limited info you gave us.

Three questions:
1) How big is the sump and what will you have in it (ie. skimmer, refugium, ect)
2) Will the return pump be the only thing that moves water in the 3 30g tanks?
3) What will be in the 3 tanks?

Flow in the sump is determined by tank drain flow and the in sump pump. If it's just some filtration (socks or media) and a skimmer, then any flow thru the sump is preety much OK. If you have a refugium or DSB you want to turn over the fuge & DSB at something in the 5-10 times per hour. You can still have more flow thru the sump, but you'll need to isolate the fuge & DSB.

If this is the only source of flow in the 30g tanks you'll be turning them at less than 10 times per hour... probably not even enough for a FOWLR. Going to a lower flow sump pump means you'll need more flow from powerheads in all 3 tanks. How much is that going to cost?

sirreal63
02/20/2013, 07:31 AM
To answer your other question, make the return plumbing 1", if will improve flow, not reduce it. The larger the pipe, the less friction loss, up to a point. Typically going up 1-2 sizes larger than the pump outlet is best. Some pumps actually require a significantly larger piping than the outlet, Mag pumps are a good example of that.

bob1435
02/20/2013, 07:37 AM
I have the 1260 and love it.....

Modern-Revolution
02/20/2013, 02:29 PM
Well the sump is a 55 gallon. It will house a skimmer and a heater and will have a large dsb fuge. I will probably have a gravity fed phosphate reactor from one of the tanks to the sump. Also have an eheim canister that I will be using as a reactor. Probably a yellow head jawfish in the fuge dsb.

I plan on using a koralia evo 750 power head in each tank but I suppose one strong pump would be better if I could get away with it.

One tank will have a mated pair of clowns and an anemone. .. not sure what kinda... maybe bta or carpet. Probably some inverts too.

One tank will have a fire coral moray eel and whatever else I can throw in there that could coexist in a tank that size. Maybe nothing. ..maybe a starfish or something.

One tank is still open for discussion.

So maybe I should get like a 1600 gph return or something and skip the koralia s? Suggestions?

Edit: I'm about to add 13" tall baffles to the sump to give you an idea of water volume. 5-6" dsb. The 55 is 48x12wx19" tall. Should allow an inch of water to drop from all tanks if power outage.
Live rock will be scattered throughout the tanks.

tkeracer619
02/20/2013, 05:20 PM
Hold on just a second. I'm not sure how anybody can make such a recommendation on pump size with the limited info you gave us.

Three questions:
1) How big is the sump and what will you have in it (ie. skimmer, refugium, ect)
He posted a picture showing 3 tanks and a sump that is clearly a 55g.
2) Will the return pump be the only thing that moves water in the 3 30g tanks?
He stated return pump and only mentioned the 3 tanks
3) What will be in the 3 tanks?
I don't think this is particularly relevant on a 120g setup made of 3 30g displays. You will most likely be using ball valves to adjust this anyways since every system is different. If they were going to contain the same stuff the op would probably just have a single larger system

Flow in the sump is determined by tank drain flow and the in sump pump.
Its determined only by the water being fed to the tanks via the return pump, drains are irrelevant.

Going to a lower flow sump pump means you'll need more flow from powerheads in all 3 tanks. How much is that going to cost?
Roughly $13 a year. + the cost of the pumps. Its less then half compared to running the pump he has laying around which wouldn't come close to providing enough flow for the system unless hes keeping sea horses.

That was my thought process for not having to ask any more info.