Anyone using a Neotherm Heater on a "largish" tank?

[deputydog95]

I'm trying to use their 300 watt on my 112 gallon reef tank.

Ambient is my office is 75 degrees during the day and 78 at night and on weekends.

The heater is in the sump and the apex temp probe is in the display tank.

I'm finding the neotherm thermostat is off by at least 2 degrees (maybe a little higher, hard to tell as it only reads and adjusts in 2 degree increments). It also struggles to hold a consistent temp on it's own...

I've resorted to having the apex turn it on and off. Which works sort of, but I'm still not happy with the operation. I'm looking for a 5 degree pull up and I find this unit stays on literally all day struggling to keep it at 79.5 It struggles so much I can't even get it to my desired temp of 80 during the day when the AC is set to 75. It will cycle on an off in the evening and weekends when the office AC is a few degrees higher.

It is an open top and there is an AC vent over it, but this seems really odd. We thought the first one was faulty but the replacement is doing the same thing.

I've gone so far as slow my return pump to about 400gph in an effort to give the water flowing through the sump more dwell time around the heater.

It should be noted that the heater is rated for 80 gallons with a 10 degree pull up. We assumed that it should be more than adequate for a 5 degree pullup on 112 gallons.

Thoughts?

[jayball]

How much do you evaporate in a day? That is all I can think of. There is no reason for it to not keep up.

Also, there is no need for dwell time. The wattage the heater puts out makes it to the water no matter the flow past it.

[mcgyvr]

300W is simply not sufficient for your tank..
Run 2..

but first.. are you positive its not turning off when its not supposed to be..
Typically when you run one with a controller you just set the temp on the heater itself 5 degrees above the desired temp that way it won't cycle off before its really supposed to be off..

I had to run 500W on a 120 gallon tank to maintain a 5 degree delta..

[evan38109]

I had some early temperature issues before I realized that I had basically no flow around my heater. Tossed a small powerhead in the chamber with both the heater and return pump and noticed that the heater suddenly ran a lot less.

Kept detritus from building up, too!

[deputydog95]

Originally Posted by jayball

How much do you evaporate in a day? That is all I can think of. There is no reason for it to not keep up.

Also, there is no need for dwell time. The wattage the heater puts out makes it to the water no matter the flow past it.

I wasn't sure if the water was running through the sump so quickly that the heater couldn't keep up. Slowing the water down had no effect...

I have a massive amount of evap. Probably 2-3 gallons per day. There is a ceiling AC vent directly over the tank that may be contributing to this. Not sure if blocking that off, at least partially, would help.

Originally Posted by mcgyvr

300W is simply not sufficient for your tank..
Run 2..

but first.. are you positive its not turning off when its not supposed to be..
Typically when you run one with a controller you just set the temp on the heater itself 5 degrees above the desired temp that way it won't cycle off before its really supposed to be off..

I had to run 500W on a 120 gallon tank to maintain a 5 degree delta..

I have the heater set at 84 degree so that the tank will try to get to my desired temp of 80 degrees. The heater seems to be off by 2 degrees so I figured that is a safe temp setting on the heater in case something weird happens and the controller stops while the heater keeps running.

Here's my apex programming:

Fallback OFF
If Temp < 79.8 Then ON
If Temp > 79.9 Then OFF
If Temp < 70.0 Then OFF
If FeedA 005 Then OFF
If FeedB 030 Then OFF

Originally Posted by evan38109

I had some early temperature issues before I realized that I had basically no flow around my heater. Tossed a small powerhead in the chamber with both the heater and return pump and noticed that the heater suddenly ran a lot less.

Kept detritus from building up, too!

Flow is great in the sump. Even slowed down I'm running around 500 gph through it and there's a skimmer running around 250gph next to it.

[jayball]

Originally Posted by deputydog95

I have a massive amount of evap. Probably 2-3 gallons per day. There is a ceiling AC vent directly over the tank that may be contributing to this. Not sure if blocking that off, at least partially, would help.

2-3 gallons a day is a lot of evap, that is where your heat is going. Can you flip the vent over the tank so it is not blowing on the water?

Why do you want to keep it at 80* ? Many keep their tank a few degrees cooler than that.

[deputydog95]

Originally Posted by jayball

2-3 gallons a day is a lot of evap, that is where your heat is going. Can you flip the vent over the tank so it is not blowing on the water?

Why do you want to keep it at 80* ? Many keep their tank a few degrees cooler than that.

We're going to take out the simple mesh ceiling tile over and put a diffuser in it's place. That should disperse the air coming in over the tank, versus blowing straight down on it.

I've had good success running at 80 in the past, so I figured I would continue on this tank. Although my LFS does some maintenance for me and browbeat me on Friday to dropping it to 78.5 lol.

I'll give that a shot and see how that works out. I'm just a little apprehensive though about running a lower temp in case my AC goes out. It will be a much larger heat swing up as it's always quite hot here in Florida. We get very few cold patches where it's under 70 degrees and it's for a couple days at best.

[bif24701]

Originally Posted by deputydog95

I'm trying to use their 300 watt on my 112 gallon reef tank.



Ambient is my office is 75 degrees during the day and 78 at night and on weekends.



The heater is in the sump and the apex temp probe is in the display tank.



I'm finding the neotherm thermostat is off by at least 2 degrees (maybe a little higher, hard to tell as it only reads and adjusts in 2 degree increments). It also struggles to hold a consistent temp on it's own...



I've resorted to having the apex turn it on and off. Which works sort of, but I'm still not happy with the operation. I'm looking for a 5 degree pull up and I find this unit stays on literally all day struggling to keep it at 79.5 It struggles so much I can't even get it to my desired temp of 80 during the day when the AC is set to 75. It will cycle on an off in the evening and weekends when the office AC is a few degrees higher.



It is an open top and there is an AC vent over it, but this seems really odd. We thought the first one was faulty but the replacement is doing the same thing.



I've gone so far as slow my return pump to about 400gph in an effort to give the water flowing through the sump more dwell time around the heater.



It should be noted that the heater is rated for 80 gallons with a 10 degree pull up. We assumed that it should be more than adequate for a 5 degree pullup on 112 gallons.



Thoughts?

I run a 800 watt titanium Finnex controlled via Apex. Gets the job done very well.


Aaron

[deputydog95]

Originally Posted by bif24701

I run a 800 watt titanium Finnex controlled via Apex. Gets the job done very well.


Aaron

What's your ambient air temp and tank temp?

[bif24701]

72/79.5


Aaron

[bif24701]

What is your total volume?


Aaron

[deputydog95]

Originally Posted by bif24701

What is your total volume?


Aaron

112 in the display tank and I believe 20 in the sump. Ballpark. Say 135 to be on the safe side.

[bif24701]

Originally Posted by deputydog95

112 in the display tank and I believe 20 in the sump. Ballpark. Say 135 to be on the safe side.

Get the 500 watt and control with APEX, so much better! Keep the sensor in same compartment as heater, but separate in distance. That way if there is no flow the heater doesn't cook stuff.


Aaron

[deputydog95]

Originally Posted by bif24701

Get the 500 watt and control with APEX, so much better! Keep the sensor in same compartment as heater, but separate in distance. That way if there is no flow the heater doesn't cook stuff.


Aaron

Heater seems awfully inexpensive. Are they any good?

[dweber618]

I run the 300w neotherm on my 100gallon cad lights, my water volume is just about what yours is and I have no problems with it keeping up. I also have a 200w accutherm (glass heater) as back up. My evaporation is a lot less than yours though. I have no problems with is staying on consistenly. It was running close to 80 with no problems, but I recently lowered my tanks temp to 76/77.

[bif24701]

Originally Posted by deputydog95

Heater seems awfully inexpensive. Are they any good?

They are the best. They are inexpensive because they must be used with a controller.


Aaron

[bif24701]

Also, they don't break, they conduct heat straight to water and not through glass or plastic, don't corrode, and they heat faster.


Aaron

[deputydog95]

Interesting. I've got the apex so this may be a good solution.