FOWLR Tank too hot??

[capital1983]

Hey All,

I just got my live rock this past Fridaya and have set up my tank. I have turned on my lights to make sure the light cycle works and I wanted to see how hot the temp would get throughout the day. I have a 716watt Metal Halide/T5VHO setup sitting on the rim of the tank on a rimless tank. The water level in the tank is about 2 inches below the rim. from light to water is about 5.5" to 6". The light cycle is T5s come on at 1pm MH's come on at 2pm and turn off at 8pm, T5's turn off at 9pm. At 9pm I registered a temp of 82.9 F for 2 nights. in the morning when I wake up, the temp is about 77-78F.. The 300watt heater doesn't even need to turn on right now. The air conditioners are not on right now either as we are just getting into the spring weather here in NJ. I don't think I should be worried even if I wanted to keep corals later on down the line. I just wanted to comfirm with the Santuary Community if the temp will be ok for my FOWLR tank for the time being. I suppose I could buy a small clip on fan for the sump if that will help at all.

 

[DaveK]

The temp your getting is on the high side. Not an emergence, but it would be better if it were a bit lower.

Adding fans across the surface of the sump and the tank can help a lot. You will get an increase in evaporation. Consider an automatic top off.

MH's places 6 inches from the water can be a big factor. Personally, I keep mine about 15 inches above the water.

Of course, if money is no object, a chiller will keep the temp spot on, but before you do that, try the fan options. They are inexpensive, and if they work, you shouldn't need a chiller.

 

[ddelozier]

MH closer than 10" off the water will heat your water dramatically without a fan.

 

[capital1983]

Ok, so what I did tonight was take some left over eggcrate that I had and laid it on top of my sump. I then took my old college dorm room fan and laid it on top of the eggcrate and turned it on high. I attached a timer that I had on hand and will have the fan turn on from 2pm to 8pm on the sump only. I am hoping that this will counteract the heat from the MH. The heater I turned to 80F to hopefully keep the temp constant and maybe drop a degree or 2 at night.

 

[mcarroll]

Just a thought...

Why so much light over a fish tank? A very basic LED fixture (e.g. Marineland Single-Bright or Double-Bright) would do the trick and eliminate any heat concerns (and most algae issues) at the same time. Smart!

When the time comes to add photosynthetic animals (or plants) you can put some more power over the tank. Until then you're kinda wasting bulbs (and power...but that's cheap) just to grow algae.

Good luck!

-Matt

P.S. This time of year when the AC/Heat isn't running (Spring and Fall usually in our neck of the woods) is usually the hottest your tank will run because humidity rises with the lack of air circulation and slows down evaporation (aka cooling) from your tank.

 

[capital1983]

Just a thought...

Why so much light over a fish tank? A very basic LED fixture (e.g. Marineland Single-Bright or Double-Bright) would do the trick and eliminate any heat concerns (and most algae issues) at the same time. Smart!

When the time comes to add photosynthetic animals (or plants) you can put some more power over the tank. Until then you're kinda wasting bulbs (and power...but that's cheap) just to grow algae.

Good luck!

-Matt

P.S. This time of year when the AC/Heat isn't running (Spring and Fall usually in our neck of the woods) is usually the hottest your tank will run because humidity rises with the lack of air circulation and slows down evaporation (aka cooling) from your tank.

Hey MC,

I cant afford a good set of LEDs at the moment. I am well aware of the capabilities, but for the time being I got the MH's so when I eventually move out of my apartment I can switch the tank back over to my most desired reef tank. as of right now, I put a fan on my sump with a timer that turns on only during my MH cycle which is keeping the tank at a constant 80 degrees. As for evap, I am not too worried about it as I always have 32 gallons of RO water ready to go. Eventually when I save up more money I am going to look into purchasing a pair of good LED's, but for now, all is well and tank is cycling better than I can imagine! Should be up an running in the next few weeks.