Temp Increasing

Hello,

I have a 75 g tank connected to a 25 g sump. My lighting is 4 54W Bulbs inside a wooden hood with an open back. (2 Actinic lights on for 12 hours, to day lights on for 10 hours, controlled with a Reefkeeper 2 controller) I have been tracking a consistent rise in the tank temp during the day. Starting at about 79 deg F in the morning and ending at 83 when the whites turn off.

How much temp rise is acceptable during the day? I could add a fan to the sump or to the hood, but is it necessary?

I have searched for Temp rise in the archives.....

Thank you;

Joe

 

My tank gets up to about 83 as a high during the day too.
I guess it depends on what type of corals you are keeping as to whether or not they are going to be affected.
Adding a fan to the sump would work as you have suggested, I think a large swing in temperature is more detrimental than just being at the top end of the range........Make sure your heater is not staying on and causing a problem, that has happened to many people here including me
Awaiting other opinions.............................

Jim

Welcome to 3reef!!! Karma to you

 

I would put a fan in somewhere? Maybe at the open where the lights are? I think certain undesirable algaes are fueled by warmer-than-normal temps. My tank gets that hot during the day also so I put a small PC fan right on the lights and the tank stays at a constant 76-78 24hours. I don't have a heater though and am puzzled as to why the temp stays constant like this. I think the 24hour run UV acts like a heater. I know I'm probably taking risks but right now here in FL panhandle it has been pretty warm. I do have a couple of heaters sitting in the closet-I'm getting off track.
Probably best to get a fan that comes on with the lights and pulls the heat out the back.

 

Good thought about the heater. I did wonder about the 2 150w heaters that I had.... Replaced both with a new 300 which is also switched off by the RK2 system at 78 deg F (the heater's thermostat is set at 80 deg F). I also installed the heater in an area where it is easier to see in the sump. It has not been on at 79 deg F in the morning when I have checked it.

I have set the RK2 with a safety temp shut off of the white lights at 83 deg F. The tank has been up for 3 months but the RK2 was set up last week. Now that I'm getting good information at a glance, I may be overly concerned. As the T-5 lighting is all custom, adding a couple of 120v PC fans can be done easy enough, but they need to be quiet....

Jim, what is your tank temp in the morning, before the lights come on? Are u seeing a 4 - 5 degree rise as well?

All of the corals and fish look fine. I see new propagation of the Zoos & the forest corals occuring.

 

Yes, I have about a 4-5 degree rise in temp throughout the day. This is normal for my tank wihout a chiller and using metal halides. My wife did not like the 500 dollar electric bill she got in the mail the other day and raised the thermostat to 80 on the air conditioner.

Jim

 

A 150 watt heater should be all you need on a 90 thats all I ran. unless the ambient temps of the room gets really cold ? then you need to figure the temperature rise and recovery rate of the heater.. And a P.C fan is not what I'd choose .
I get them from a supplier But W.W Grainger Co has some nice Coaxial one's 215 CFM and 120 and 240 V and you want them to blow into the hood or one in pushing in and one pulling out I just on a 90 with 2 48in VHO and 2 175 M/H's an ambient room temp of 72 to 73 F just used one in the very center of the hood blowing into the hood. That way you cause more evaporation and the pressurized air blows the hot air out the end. These fans are what we use in the HVAC industry for convector wall heaters and in jet Liners to move conditioned air through thoses little tube over head Just a thought..

 

A fan (or 2) would certainly be the most cost effective way to control your tempature fluctuations- set it to run with your lights and you should be very happy with the results!

 

Ive got a 90 with 4x54 and 2x250MH in a canopy. Canopy with a 4" opening on the back. I keep a 6" small desk fan (few bucks at wally world) on the same timer as my actinics (first on, last off). Keep the fan pointing into the tank as best you can. Even if its running parallel to the opening, whatever, it will help a lot. Temp will rise 1 degree F throughout the entire day. (for me)

EDIT: I've found the above to work far better for me than using the same fan over my 2x10gal sumps.

Food for thought, HTH.

 

Ok, thank you all. I will aquire a fan for the hood this weekend and run it with my actinics.

On a side note, but related, my tank has glass pannels on top and about 3" below the lights. There is a note on the hood not to operate the system with out the pannels in place. As glass diffuses light (even more so as the salt builds up during the week) this will cut the effectiveness of what little light I do have.

Do you run with or with out glass pannels on top of the tank, and how far are the lights from the surface of the tank?

Thank you;

Joe

 

I'd remove the glass Tops ASAP a problem in the making it will lock in CO'2's and keep O'2 out never ever use tops on a tank o any kind is what i have found to be best all they do is slow evaporation and increase heat and retard its removal and as i said holds CO'2s in at night.