Keeping temps stable...

[ellisz]

Hi all,

I figure I have about 100 gal of water with my tank, sump and fuge. I bought a Rena Cal Excel 300 watt heater and I also have a 150 watt heater as helper/backup. I do get some heat from my MH's but I try to keep my tank at 82. My tank will be 80 in the mornings and will hit 84+ at 10 PM when the MH's go off. Weird things is the heater light will be on when it is 84!

My heaters are in the sump and I have a digital thermometer in the display. I have 2 80mm fans blowing out the top of the canopy and I have a 120mm fan blowing in from the back at water level.

I feel the Rena Cal heater is messed up but with the heaters I have, should this be a problem keeping up? The high temps I am working on but the low temps are driving me crazy. I adjusted the temps up yesterday but ended up with 86 degree water when I got home! My room temp is 70-72.

Any ideas?

 

[dustybrannum]

mine fluctuates from 78 at night to 82 in the afternoon cause of my MH's. that is the temp in the sump itself where my heaters are. i have two 4 inch fans pulling air over the tank and keep the room temp at 74. i am just planning on getting a chiller before next summer so maybe i can run all 3 of my MH's instead of just two. i use three heaters set at 79 to keep mine at 78 at night. i may try and set my air conditioner in the tank room to only run when the lights are on that way at night the temp does not drop as much but if the temp does not lower then the overall high temp would probably adjust to that much higher so your overall difference is the same as in 78-82 could end up being 80-84. good luck with what ever you find to try.

 

[swissfish]

most of the time, the Sump and Tank temp differ.
Make sure you are checking the tank temp.

 

[Brad]

You know, I just always assumed that the sump and tank would be the same temperature....I'll check that out...

 

[Crawling68]

I have thermometers in the tank and sump to monitor. The tank is always hotter because of the halides. I have mine setup with the heater in the sump, but it is set to come on when the halides go off. My tank stays at 79-80. Its kinda weird, the cooler sump water cools the main during the day, then the heater in the sump warms the tank at night.