Mag 12 in basement sump for closed loop

[Scouter Steve]

I was planning on using the mag 12 pump I have for a closed loop in my new setup with a basement sump. Originally I had planned the mag in the stand as for the closed loop but found it does leak a ton. So now my question is will I get a head loss if it drops an extra 4-5 feet in the closed loop by keeping the pump in my sump or if this is countered by the water dropping from the tank?

[sasquatch]

Approx 1000 gph at 4' head, yes you still have to shove the water up 4 feet, the mags seem to be pretty stable at rated gph, not to forget every turn steals a bit too.Steve

[lcstorc]

Here is a head loss calculator. It may help.
http://www.aquaticeco.com/index.cfm/....calc_pumphead

[Scouter Steve]

I know about head loss in a normal return pump but they don't exit the tank and enter in nearly the same spot. In your sump the return pump is pushing up the total height but a closed loop has the energy of the dropping water. If the closed loop were at tank level I know there is very little head loss, same as a few inches below the tank. I was wondering what it would be like with a 6-7 foot drop.

[prow]

you will have no head loss at all due to height. the water pressure its self, via gravity, will be equal with in the closed circuit. the only head loss you will have is in the tubing when you try to push water through it. friction loss. a 45 degree angle will add less friction loss than trying to pushing that same water through a 90 degree angle. the length and size of tubing factors in too. the longer it is the more friction. the only other thing is the where the loop exits and enters the tank. the water at the bottom of the tank will be heavier than the water at the top. but this is marginal in most tanks. if its entering and exiting near the top of tank we dont even need to consider it. JMO. use this calculator and just put 0 on the verticle. http://www.reefcentral.com/calc/hlc2.php

[bluespotjawfish]

Thanks Prow, this is the first calculator I could figure out either how to use or how to understand the results. Just reconfigured my setup yesterday so was curious what changes occurred.

I don't know nothin' about closed loop systems, so thanks for letting me impose on your thread! Good luck to you in finding your answers. Sounds like Prow has you headed in the right direction.

[sasquatch]

Thanks Prow!Our personal beliefs are the hardest to let go of,after reading your post and going "huh" I went on a read/search hunt and now stand corrected some of the articles hurt my brain(damn you! lol) some things like Santa and moon cheese ill stick with Steve

[mps9506]

Citto to what prow said.
Just to add in my experience though...
I tried a couple of mag 12's for closed loops on my old tank. They were everything but a good closed loop pump. They were noisy and I'd always find some salt creep around them. when I finally replaced it with a true external pump i was much happier with the noise, and a major temperature drop as well.
so as a future upgrade you may want to look at replacing it with a true external pump designed for closed loops, it will make you happy

[prow]

thanks guys and your very welcome. Steve, yeah sometimes the turth hurts but lets no forget, its the wise man that listens.

[sasquatch]

must be the ear wax then lol

[Scouter Steve]

Originally Posted by mps9506

Citto to what prow said.
Just to add in my experience though...
I tried a couple of mag 12's for closed loops on my old tank. They were everything but a good closed loop pump. They were noisy and I'd always find some salt creep around them. when I finally replaced it with a true external pump i was much happier with the noise, and a major temperature drop as well.
so as a future upgrade you may want to look at replacing it with a true external pump designed for closed loops, it will make you happy

Noise is not an issue with this set up and you are 1000 % right on the creep (mine about gushes!). Thing is, I already have it so it is cheapest. With a true external I would have it in the stand beneath but this one, for now, will be dropped into the sump just so it can leak all it wants. I will still have an over the back drain and my return loop. Just the pump will sit in the sump. Heat is not an issue with my chiller and the fact it is a basement sump which so far is keeping my tanks heater on most of the time.

[mps9506]