Mag 18 - Advise Needed

[DBlackman]

Hey,

I am using a Mag 18 for my 'Return pump', which keeps the 'Day time' water temperate in the tank at 80.1 degrees. I have noticed that the 'Day time' water temperate had increased to 83.1 degrees on Sunday. The house temperature was 75 degrees, at the time the water temperature was noticed. I am currently using a 1/2 JBJ Chiller on my 120gal, which is set to turn on at 79 degrees.

I need advise on keeping the water temperature below 81 degrees, without having to upgrade the chiller. Summer is just around the corner!

Would raising the Mag 18 above the water level of the sump be a problem?

HHHHEEELLP!!!

[kaiser]

Get a fan and mount it to blow into the top of your sump, it'll cool it down.

[Bill S]

How big a tank/sump are we talking about?

[jc]

Is it possible to downgrade to another mag?

[Bill S]

Unless the tank is 100 gallons or less, you shouldn't get THAT much heating from the Mag... In which case, 1/2 hp is overkill. I'm guessing that you have an overheating pump. Could need cleaning?

[greenmako]

Mag pumps run hot you could try switching to an ehiem or an external pump that would help. Since you are seeing an increase in heat that is out of normal then like Bill said it may need some cleaning.

[DBlackman]

kaiser, I went out and purchased a 7 inch 'clip on' fan from Walmart this afternoon to blow air on the Halide. To include a small 3 inch fan blowing over the sump.

bstreep, The tank is a 120gal 4 x 2 x 2 and the sump is approximately 35gals [purchased a RCA - the sump w/refug combo model]. I will clean the pump tomorrow morning.

jc, The Mag 18 is 'Feeding' the CA Reactor, Chiller, and SWID. Down-grading is not an option. However, I may need to go back to using two (2) Rio 17HP.

greenmako, I heard that Ehiem's flow rates were inaccurate, BUT worth researching again.

[greenmako]

I may need to go back to using two (2) Rio 17HP.

Watch out for Rio's I have read some horror stories of the Rio's failing and releasing oil into the water, which you can search for on RC. I had one fail in a bucket that I was mixing up fresh saltwater in and the pump was less than a month old. So just a heads up

[DBlackman]

I have been told and read about the problems with Rio 36HP, which are no longer being manufactured. So, when BigBird had the Mag 18 for sale.... I jumped and took out the Rio 17HP/s, put back in their original boxes, and stored them in the garage for 'Just-in-Case'. I'am thinking of 'trading' the UV I have for sale, for a large Eheim pump or just use the proceeds to buy one. Time will tell.

[kaiser]

The Mag 18 is 'Feeding' the CA Reactor, Chiller, and SWID. Down-grading is not an option.

I am wondering if you don't have too much of a load on that pump creating too much back pressure. I am having a similar Problem with a Mag12 for return and a Mag7 for Skimmer sitting in my sump. I added a fan and it dropped the temps down just fine. I am still thinking about taking the Mag12 out of the sump and use it external.

[DBlackman]

kaiser, I was concerned about 'back-pressure' too, along with preventing 'Stress fractures' known to be experienced with Mag pumps.

I am using two (2) 1-inch 'T' in the 'Return' line:
a. The 1st 'T' directs flow to the CA Reactor, which has a Ball Value to prevent too much pressure on the CA Reactor.
b. The 2nd 'T' directs flow to the Chiller and is 'unrestricted'.
c. The rest of the main flow hits the SWID, before returning water to the tank.

I figured that the 2nd 'T' line to the Chiller would prevent back-pressure from occurring, but I am not plumber.

[kaiser]

Every T added will create more back pressure. Mags are very sensitive to that. I've read somewhere that for every t or elbow in the line is dropping the flow quiet a bit.

[DBlackman]

kaiser, Yes, I was made aware on the use of 'elbows', to include other factors on flow restriction. But the insight on the use of T/s and PVC/s or plumbing in general, were not to use materials that are smaller then the outlet of the pump being used. I figured that using 1-inch tubing and 1-inch 'T's' wouldn't be a major factor... unlike the 3/4 inch fittings on the SWID. When I take the Mag 18 out for cleaning, I will check it's condition. If there are stress fractures, then I will need to put the SWID on a separate pump or something. Just don't want to add additional electrical equipment.

[kaiser]

Does anybody here have experience with Mag 12s used as external pumps?

[tomanero]

I'm a big fan of fans blowing across the water surface for cooling.

I read in 2 other posts that because of the humidity people were having overheating problems this past weekend. Haven't had that experience myself but who knows.

[alton]

I used a mag 18 on my 75 for years but only as an external pump and never had any heating issues. But in saying that Marine Depot will not warranty mag drive pumps if you use them externally.

[DBlackman]

Hey alton, that's great information. Thanks!