heater question

[djam]

Assuming we keep our house at around 65-68 degrees, any rules of thumb on how many watts it is going to take per gallon to heat our tank? I have two 300s and a 200s in my tank and I can't seem to raise the temperature above 76 degrees. Two of the heaters are in the fuge (with the temp probe) and one in the sump. Water feels cold and corals are not happy. Thoughts? Suggestions? Should I move a heater into the main tank.

As for equipment I only have 3 powerheads (all 1500gph), skimmer (Reefdynamics 250), 2 reactors, & return pump (DC12000). Lights are 5 LED fixtures that throw out almost no heat. Tank is 8x2x2 with two sumps 3x3x2, total 420g.

I didn't have temperature issues all summer and the tank stayed at 77.6-77.8. I'm thinking I don't have enough heaters.

 

[krayzie321]

Have u Checked to see if they actually work

 

[pgr11]

Yeah something isn't right. Some on them must not be working. I've used 2 300w on my tank with no issues. I currently run an 800w with the 2 300w as dry backups. I can heat my water into the 90's if I wanted

 

[solitude127]

I'd separate the temp probe and the heaters. I would probably place the heaters in the sump area or a higher flow area and then place the temp probe in the return area. If the heater and the temp probe are close together, it might heat up that part of the water quicker than the rest of the water.
I have a 150g tank and have a 250 and 150 and it can keep up easily and my house is about 67 at night.

 

[Zoarder]

420g is a lot of water... I used 2 300 watts on my 120 and the heater was always on. I now bought 2 500 watts for my two tanks

 

[Zoarder]

I would lend you my 800 watts to give it a try but you are out there...

 

[mark.a.smith405]

I have a 300 watt titanium and have never had any issues heating my 150 (210 total). You've got to have some bad heaters in there

 

[SchnitzelReef]

I have a 250g tank and a 80-100g sump and I only have a 250w and a 300w heater. Keeps my tank up to temp no problem. Your tank and sumps are all in the house right? If so, then one of the heaters must be faulty. Obviously bigger is better, but I think u could get by with 2-300w heaters. On my tank I have one heater set at 78* and one at 77*. That way it's like a dual stage heater.

 

[TH64]

What are you using to measure the temp?

 

[djam]

I'm using a reefkeeper elite temp probe, which I validated again an old fashioned mercury thermometer. I double checked and verified a that the heater is on and hot. My old tank, which was in the same spot barely used the heater. Thinking about this I wonder if it is related to having more energy efficient equipment.

Temp probe is in the fuge #1, and heaters are in fuge #1 (300), fuge 2 (300), skimmer/return (200). I disconnected the heaters from the rk to run just against the outlet. Again they are on....at a loss.

 

[SchnitzelReef]

I'm using a reefkeeper elite temp probe, which I validated again an old fashioned mercury thermometer. I double checked and verified a that the heater is on and hot. My old tank, which was in the same spot barely used the heater. Thinking about this I wonder if it is related to having more energy efficient equipment.

Temp probe is in the fuge #1, and heaters are in fuge #1 (300), fuge 2 (300), skimmer/return (200). I disconnected the heaters from the rk to run just against the outlet. Again they are on....at a loss.

If all the heaters are working correctly, something else is up. That many heaters should keep your tank up to temp no problem.

-is any part of your tank outside?
-what kind of flow do u have going from your sump/fuge to your display? If the flow is really slow, U might not have enough turn over rate to heat the tanks water.
-do u run a chiller?

Assuming your heaters are FOR SURE working correctly, I don't see what else could be causing the tank to not get up to temp.

 

[djam]

If all the heaters are working correctly, something else is up. That many heaters should keep your tank up to temp no problem.

-is any part of your tank outside?
-what kind of flow do u have going from your sump/fuge to your display? If the flow is really slow, U might not have enough turn over rate to heat the tanks water.
-do u run a chiller?

Assuming your heaters are FOR SURE working correctly, I don't see what else could be causing the tank to not get up to temp.

-is any part of your tank outside? - nope, all indoor
-what kind of flow do u have going from your sump/fuge to your display? If the flow is really slow, U might not have enough turn over rate to heat the tanks water. - I'd guess somewhere between 2500-3000gph based on stated performance and how much head pressure it is.
-do u run a chiller? - nope and I verified the fans are off.

 

[MortgageTank]

I'm thinking 800 Watts as well. Although I don't have to heat my tank in my 2nd floor apt. Now cooling it is another thing altogether....