Circulation techniques???

[jaded]

I am getting a 135rr on Sunday. The 2 main pumps with be a mag5 and a mag7... this is a total 1200gph but at this tank height it will only push around half that. There are a couple of power heads in the tank to help but I'd like to clean the look up before I add more rock and really "scape" it.

My question is about circulation techniques. Can I improve the output of these two pump by running them in series (or any other way) as pictured here?
http://www.paddletexas.com/images/temp_images/pump_series.jpg

I'll be plumbing the return after the tank is up and running so there isnt a big rush to get answers but I'm planning several DIY projects and this one might as well get on the drawing board as well!

in the drawing below you can see 2 basic plans are for the manifold... is one way better than the other? Obviously I need to know the answer to the pump question before I can answer the manifod question.
http://www.maast.org/modules/PNphpBB2/files/loc_line01.jpg

any help would be appriciated

[Richard]

I think you should run them seperate.

Illustration #1 - I don't think pumping into the intake of a pump will increase the output.
Illustration #2 - Pumping directly into a tee would create alot of backpressure. Maybe it would work better if you used a Y connector. For your plumbing keep in mind every elbow adds about a foot of head pressure.

Honestly for a 135 I would suggest you sell the mags and go with a good external pump. Less heat in your water and better flow.

[jaded]

Its definately crossed my mind... I would have to change a lot of plans though... the 90 gallon sump takes up just about ever extra inch under the tank. If I went extrenal I'd have to chuck that plan and go with something completely different.

[Richard]

How about selling them and getting a mag 12 instead?

At 4' head the best you'll get is 790 gph out of those two pumps and it's 140 watts. A mag12 will give you 1190 gph@4' and uses 110 watts. You'll probably end up fighting heat issues like most of us and every watt (especially submersed) counts.

[Tim Marvin]

Good point Richard. I beleive CB pets also sells Sequence pumps, a dart would be awesome.

[RobertG]

My mags have always heated the water, believe it or not this is how I heat my water for water changes. I drop the mag 24 in the 45 gallons of water with salt, then let it run for 3-4 hours. 68 up to 85 in a couple of hours. An external pump is really much nicer, especially if you have heat issues already.

[NaCl_H2O]

... 68 up to 85 in a couple of hours.

lol ... you apparently get full use out of all of your equipment ;)

[GaryP]

Couldn't you set an external pump behind the stand on the floor? I'd set it on a couple of pieces is scrap lumber to get it up off the floor in case of a spill.

Richard is definitely correct on using Y's instead of T's. I plumbed mine with tygon tubing instead of PVC to avoid having to use a lot of elbows for the same reason.

[jaded]

I'll be getting the system on sunday, at that time I'll see how it all works out. The 90 sump wont be ready to be used at this time anyway. I'm going to set it up"as is" for now. I can save a few bucks for a new sump and pump, then sell off the old stuff when that happens

anyone got a sump and pump they dont need :-)

[jaded]

SO I'm looking into the cost of external pumps... I'm thinking it's probably a good idea to buy new unless I find a heck of a deal here.

what would you suggest I look into???

[bprewit]

I am curious about connecting the discharge from one pump to the suction of another. I know this, friends jetboat used a large impeller of course but also uses a smaller impeller that came from a jet ski to charge the main impeller. He bought the kit to do this and claims a large increase on speed as well as launch. I am not sure though what the outcome would be with the mag pumps. Be worth trying just for grins but seems to be wasted energy and excessive heat in the long run but also pumps arent cheap and sometime have to do odd things to get by.