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Chill or Not Chill that is the question

I have 2 overflow boxes on each side, each pump is driving an individual return using 3/4" tubing. They sit in the sump completely submerged in water.

OK, I think I've got a better understanding of your setup, it's not a drilled tank. I would have been surprised if it was since I don't believe that the overflow bulkheads in a reef ready tank would keep up with the amount of water that those Mag 12's would be pushing up into the tank. Assuming that your temp readings are accurate, although they're not critical, I would do something to get them down, without the assistance of a chiller. Fans will do some good, but without something to control them, you'll just have to let them run all the time. If you have any glass or plastic cover on your tank or sump, I'd remover them. If it were me, I'd replace the Mag 12's with Mag 9's. You really don't need all that flow through your sump anyway, and the Mag 9's will run cooler. Along with the returns, your Mp 40's should provide you with a lot of circulation.

Another option would be to go to an external pump.
 

redfishbluefish

Officer Emeritus
Officer Emeritus
Something’s not kosher. 82 degrees with LED’s?? How hot is the room? Granted, MAG 12’s consume 110watts each, but that still wouldn’t cause 82 degrees this time of year. I’m running T5’s with a MAG 24 and MAG 9.5 and have no problem with heat this time of year.

Anyway, a fan or multiple fans is an excellent way to cool the tank. I’m running two fans on my tank….one across the T5 lights – surface of the tank and the second blowing down on the sump. And yes, it does cause for additional evaporation…but the cooling benefit is well worth the loss of water.

I do not have a chiller. During the summer I have a window air conditioner set at about 72 degrees that keeps the tank cool…..maybe a high of about 80. I haven’t had the air on for the past three weeks or so.
 
Think I made a mistake in the description, my tank is drilled with two corner overflows. I completely agree that the MAG12s might be the problem. I am experimenting today with a new thermometer (going to buy one this morning) and by shutting down one of the pumps. If the problem is gone its decision time, new pumps or drop to a single pump.

Putting fans in the canopy is a definite as it can't hurt.


Everyone provided great feedback, really appreciate it.
 
I shut down one pump and my temp is down .4 degrees. What a PITA.... I am thinking of moving away from the magdrives all together and grabbing something that uses much less energy.
 
If you have a drilled tank then the Mag 12's could have another potential problem. The standard size bulkheads that are drilled for your overflows are 1", and are rated for a "safe" flow of 600 gph. I know that is a conservative figure, since I'm putting about 750 through mine. With the Mag 12's, considering about 5' of head loss, you must be pushing about 900 gph into each of those overflows, which is 50% higher than what they recommend. So, assuming all this is accurate, there is a potential for flooding if you have any type of obstruction.
 
I see you tried shutting down one pump. Try the other one also maybe one pump is overheating. And stick another thermometer in there to make sure the temp is correct.
 
I appreciate the feedback. I am going to grab some smaller return pumps as i just tested the water near the Mag12 and its reading 84 so that is definitely my problem. No decision time on new pump, tunze, octopus or mag9......
 

magic

Officer Emeritus
Officer Emeritus
Fans blowing across the top of the water surface. This will cause evaporation. The more evaporation the cooler the water. You can also put a fan blowing across the top of your sump.

+1 This is a cheap and effective fix.

Bob
 

redfishbluefish

Officer Emeritus
Officer Emeritus
If you have a drilled tank then the Mag 12's could have another potential problem. The standard size bulkheads that are drilled for your overflows are 1", and are rated for a "safe" flow of 600 gph. I know that is a conservative figure, since I'm putting about 750 through mine. With the Mag 12's, considering about 5' of head loss, you must be pushing about 900 gph into each of those overflows, which is 50% higher than what they recommend. So, assuming all this is accurate, there is a potential for flooding if you have any type of obstruction.


If I’m not mistaken, a “standard” overflow in this size tank has a 1” diameter pipe going down to the sump and a ¾” return. Gravitational flow through a 1” pipe is roughly 660 gph. This is a rough estimate assuming PVC pipe and relatively short distance with minimal elbows, valves and unions. The head loss for the water getting pumped back up can accurately be determined HERE, inputting the exact setup.



Now back to the problem….A big +1 on use of fans…..The cheapest way to lower temperature. As far as that one MAG heating up a 180 gallon setup four degrees, I’m guessing it is either gunked up with smutz or has a bad shaft/impeller. Even though MAGs are energy hogs, a well running MAG shouldn’t put that much heat into the system. I’d pull that pump apart and give it a good cleaning, checking the shaft/impeller condition. You still can’t beat a MAG as far as dependability. If need be, pick up a new impeller in the group buy. Just make sure you get the right version. Here’s the older style VERSION A and the newer style VERSION B.
 
If you have the room, i would really recommend that you go with an external pump. You would need to drain the sump and get it drilled. But then you know that your pumps will not effect the heat of the water. I would rather run the heater and have a little more control over it.
 

redfishbluefish

Officer Emeritus
Officer Emeritus
Paul, put your reading glasses on that is 0.4 degrees. :p

Hey, why do you think I enlarge the stuff I post! :eek:


Actually I got the four degree difference assuming his target temperature was 78, and the tank was getting up to 82. If we take Brian’s decimals into account, it actually is 4.4 degrees. But what’s a few tenths amongst friends? I round off or truncate to whole numbers.
:grin:
 
I'm in agreement with using a Mag pump, but would replace the 12's with the 9.5's for both the heat issue and the potential for flooding. The fans are a good idea too, but I would control them through a reefkeeper or apex and have them come on only when the tank temp gets to a predetermined threshold, otherwise they are just running all the time.
 
I don't think the pump should be running that hot. Again try to switch that one off and run the other one. I run one Mag 12 on my 120 and right now it is at 81 but I have T5 lighting and some less efficient pumps then you.
 
Problem identified:
I have run each Mag12 independently for 12 hours. Pump A maintains a temp of 82.5 in the tank, while pump B has let the water temp drop to 80 over night. I have already contacted the company i purchased from that I want to return the defective one and buy two new different pumps, my gears less than a month old.

I appreciate everyone's help.
 
Good luck!!! I would still if possible switch pumps and just run one pump to both overflows. That is what I did when I had my 170. With an external pump you never have to worry about the heat from the motor and it is one less thing that has electric running through your water.
 
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