Dual Heaters

[PaulHR]

Hi everyone, I need some advice on heaters. My tank is 240 ltr and 1.2m wide, I have a 300w heater on one end but I've noticed the opposite end of the tank is a little over 1c cooler than the end with the heater.

I've read a number of people have two heaters either end of the tank to help with consistency and to also have redundancy should one of the heaters fail.

For the size tank that I have, I understand 2x 200w heaters would be enough. I already have a 300w and I was wondering what the impact would be if I added a second 300w on the other end as I have a spare one. I know the thermostat would control the heater activity but would love to know if there are any reasons not to use the 300's and buy 2x 200's instead.

I look forward to your comments.

Thanks.

 

[DrRob]

Options I can think off of the top of my head.

1. Ignore it, the fish will swim where they want to.
2. Up the flow over the heater to spread warm water better around the tank, either by moving the heater or the outflow.
3. Get a second heater (as you have, and add that. 2x300W would be fine, it's underpowering heaters that causes trouble by them running constantly.

 

[snazy]

I'd say you should address the flow in the tank instead. The water is probably not moving that much around as your case it's not that the heater doesn't heat up one side to the desired temperature, but the heated water is not moved around evenly. 300W heater is more than enough for a tank this size and will not overwork itself. Two internal heaters can fool each other with a bad flow in the tank too. The best is to get external heater if you can.
I personally use one internal 300W heater on 330 litre tank and the temperature doesn't change even slightly unless I turn on the room heater, then it goes up

Try putting a small powerhead in the tank so the colder side gets moved around.

 

[PaulHR]

Thank you, you both mentioned flow and I think that is where I may have a problem thinking about it.

This is my tank set-up (It's only a couple of weeks old and my knowledge currently is quite *cough* limited at the moment but itching to learn!):

While facing the tank, the filter inlet is in the far right back corner, the heater is diagonal across the right end of the tank and the spray arm is submerged about an inch and located back left and facing the front.

Would this cause me issues? If the heater was located on the other side of tank near the spray arm, this would improve circulation? Also would pointing the spray arm to point to the opposite end of the tank help too?

 

[snazy]

Pointing the spray bar along the lenght of the tank is better, even for the fish and good surface movement for oxygen.
I've got my heater right next to the intake tubes on the right side of the tank. The filter outlet is blowing from left to right towards the intake tubes and there's no temperature difference.
Another option is the heater near the outlet tube blowing at it somehow but the way you've positioned the filter and difference in temperature already suggests you need improvements to make the water go all around the tank so moving the heater is not really such a good option.

 

[PaulHR]

Pointing the spray bar along the lenght of the tank is better, even for the fish and good surface movement for oxygen.
I've got my heater right next to the intake tubes on the right side of the tank. The filter outlet is blowing from left to right towards the intake tubes and there's no temperature difference.
Another option is the heater near the outlet tube blowing at it somehow but the way you've positioned the filter and difference in temperature already suggests you need improvements to make the water go all around the tank so moving the heater is not really such a good option.

Thanks snazy, I'll move the spray bar tonight and see how it goes. Much appreciated.

Another quick question, I have plants and a co2 unit and the spray bar is pointing directly outwards. I read somewhere that flow from the spray bar must not disturb the surface of the water to much due to the co2 which is why I've got it submerged about 1 inch under the surface so it doesn't affect the surface to much. Do you know if that information is correct?

 

[snazy]

Pointing the spray bar along the lenght of the tank is better, even for the fish and good surface movement for oxygen.
I've got my heater right next to the intake tubes on the right side of the tank. The filter outlet is blowing from left to right towards the intake tubes and there's no temperature difference.
Another option is the heater near the outlet tube blowing at it somehow but the way you've positioned the filter and difference in temperature already suggests you need improvements to make the water go all around the tank so moving the heater is not really such a good option.

Thanks snazy, I'll move the spray bar tonight and see how it goes. Much appreciated.

Another quick question, I have plants and a co2 unit and the spray bar is pointing directly outwards. I read somewhere that flow from the spray bar must not disturb the surface of the water to much due to the co2 which is why I've got it submerged about 1 inch under the surface so it doesn't affect the surface to much. Do you know if that information is correct?

Honestly, I have no experience with CO2 so I don't think I'll give you any suitable advise. Try posting in the planted section of the forum. Plenty of good members there.

 

[PaulHR]

Pointing the spray bar along the lenght of the tank is better, even for the fish and good surface movement for oxygen.
I've got my heater right next to the intake tubes on the right side of the tank. The filter outlet is blowing from left to right towards the intake tubes and there's no temperature difference.
Another option is the heater near the outlet tube blowing at it somehow but the way you've positioned the filter and difference in temperature already suggests you need improvements to make the water go all around the tank so moving the heater is not really such a good option.

Thanks snazy, I'll move the spray bar tonight and see how it goes. Much appreciated.

Another quick question, I have plants and a co2 unit and the spray bar is pointing directly outwards. I read somewhere that flow from the spray bar must not disturb the surface of the water to much due to the co2 which is why I've got it submerged about 1 inch under the surface so it doesn't affect the surface to much. Do you know if that information is correct?

Honestly, I have no experience with CO2 so I don't think I'll give you any suitable advise. Try posting in the planted section of the forum. Plenty of good members there.

I'll do just that, thanks snazy.