Overheating Tank

[Ol' Studly]

I have a 125 soon-to-be-reef that is having temperature problems. The tank has been sitting practically idle while I was redoing the lighting. Now the lights are ready, but here's the problem . . .The tank is staying 86 degrees with no lights! Here's the setup:

125g drilled AGA tank
Ecosystem 3616 sump w/ a 2x65w Orbit PC light (always on)
Iwaki MD70RLT return pump (1,500 gph)
3 MJ 1200 powerheads on a Wavemaster wavemaker
AC Thermostat stays around 73

If I put my hood (3x400w MH w/ 2 6' VHO actinics) on this I'll have chowder! I thought I might eventully need a chiller w/ the hood, but should the tank be this hot now? All suggestions welcome. Thanks.

 

[Craig Lambert]

That doesn't sound right. I would double check the temp with another thermometer. If it is really 86 degrees, the problem has to be with the Iwaki pump. I'm not knowledgeable as far as the MD70RLT, but I thought larger Iwaki's were fan cooled rather than water cooled. I don't think the MJ's could add much heat.

 

[Ol' Studly]

I checked with an instant read thermometer from the kitchen and got the same thing. The Iwaki doesn't feel hot to the touch.

 

[Craig Lambert]

Well then...probably best to work by process of ellimination. I would shut off the iwaki, and let the maxijets run. Then check the temp after a few hours. You might then do the reverse...shut down the maxi jets and run just the iwaki.

 

[navajo]

Just to add a bit. When I was using Maxijets, they DID increase the water temp quite a bit (probably because I never cleaned them...) My Iwaki doesn't seem to add any heat though.

HTH

 

[AndyB4784]

really, i have 3 maxijet 1200 in my 50 breader and a seio 620 and my temp is constant at 80 (open top with MH lighting). wouldn't think that would be it... check with a third thermometor. seems like with all of that water to displace the heat it would be a non issue.

 

[SDguy]

<a href=showthread.php?s=&postid=8316268#post8316268 target=_blank>Originally posted</a> by AndyB4784
really, i have 3 maxijet 1200 in my 50 breader and a seio 620 and my temp is constant at 80 (open top with MH lighting). wouldn't think that would be it... check with a third thermometor. seems like with all of that water to displace the heat it would be a non issue.

Comparing different people's tanks is pretty useless. Ambient temperature, fans, stand/canopy ventilation, all play huge roles. So unless the systems are exactly the same (including cooling fans and the like) AND ambient room temp is the same, it's not going to tell you much.

Craig Lambert has the right idea...process of elimination. I would, however, wait 24-48 hours between changes to make sure you have a good, stable temp reading. I went through this myself....you can see what I did here

hth

 

[Ol' Studly]

Thanks for the replies. I had already added a 9" fan in the stand yesterday morning. I turned off the PCs for two hours yesterday and there was no change. Reading the responses, I probably should have left the light off longer. This morning I turned off the Wavemaster. I'll see how that does.

SDGuy, I couldn't tell from the link, what did you end up doing in your situation? I know you solved the problem, it just wasn't clear to me which advice you took. Thanks.

 

[Ol' Studly]

Just checked the temp. 81.7 F. Turned the PCs back on. I'm not sure yet if it was turning off the lights and wavemaker or adding the fan. We'll see . . . Just got a call this morning that the glass for my hood arrived . . . I hope I have things ready now.

 

[Craig Lambert]

When you say glass for your hood, you don't mean glass top for the tank do you?

 

[SDguy]

Yeah, I suppose I should finish off that thread. So this is what I ended up with:

Two 4" fans blowing into the canopy. The entire back of the canopy is open. Three 4" fans blowing into the stand (one directly onto the back fan of the hammerhead). Multiple holes in the other side of the back of the stand for the hot air to escape. On the hottest day of the summer (well over 90F), with all equipment running, and all the fans on, the tank hit around 89F. So then I knew I needed a chiller that only had to pull down about 7-8 degrees F on the hottest of days.

hth

 

[Ol' Studly]

<a href=showthread.php?s=&postid=8326556#post8326556 target=_blank>Originally posted</a> by Craig Lambert
When you say glass for your hood, you don't mean glass top for the tank do you?

No, the hood came with a 6' acrylic lens that was fried by the MH lights, so I'm putting in two 3 ' pieces of 3/16" tempered glass. The top of the tank is open. BTW the room temp is actually around 80-82 F so I think I'm ok for now, I'm waiting to see what the PC lights on the sump do.

SDguy, why do you have both canopy fans blowing in? My LFS is tellling me I'll need one blowing in and one blowing out to draw through the canopy. Just curious. Thanks guys.

 

[SDguy]

<a href=showthread.php?s=&postid=8327095#post8327095 target=_blank>Originally posted</a> by Ol' Studly
My LFS is tellling me I'll need one blowing in and one blowing out to draw through the canopy. Just curious. Thanks guys.

Yes, if there are no other openings in the canopy, this is best. But my entire back is open, so I have my fans blowing in at the corners. The air then travels back out through the center. IMO, it's easier on the fans not to be sucking humid/salty air out from the tank. You'll find people with opinions favoring both methods.

 

[Ocicat]

I just set up my tank in August, and I found that my Iwaki MD100RLT adds significant heat to my water. Before I ever put lights on the tank, the temp was 83-84. The only other things in the tank were the ASM G3 skimmer and two MJ 1200's. This is also despite the fact that my sump is in the basement, which I expected to help cool the water. With lights, my tank was 85-86 during the afternoon. (This actually did not seem to bother the inhabitants... but it made me nervous.)

The weather seems to have a significant impact on the tank temp, so I guess there are greater swings in my ambient house temp than I am really aware of. It isn't like I let the house get hot or even really warm, but I don't blast the AC either. Now that the weather has turned cooler (high of 59 today), my tank temp is running at 81, which suits me fine for now... At least I don't have to worry about a heater going haywire. :-\ I think that when the weather warms up again I will have to think about a chiller, or else keep my house A/C on pretty high.

Anyhow, it has to be the Iwaki, as there really is nothing else. I bought it used, and it could probably use a cleaning, which I imagine might help.