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Discussion Starter · #1 ·
I am setting up a 90g acrylic tank 48Lx18Wx24H. It will be housing Mbunas so I want it to maintain about an 80° water temp.

What do I need as far as heating goes? How many watts? Will I need more than one heater? Do I place them on the side walls?

Thanks for any help.

Gary
 

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Hi Gary,

FYIW, I have a single 300W heater in my new 90 Gallon. The house remains at a steady 71F, and the heater so far has managed to keep the water stable at 79F without running '24x7'.

Some people suggest 2 heaters to eliminate 'dead-spots' (and for "redundancy"). Me? I wanted lots of rock at the rear of the tank, two heaters = twice the risk once might get broken! Plus if all power goes out, there goes any redundancy with it!

My heater is located on an angle to the rear of the tank. temp is monitored by an external LCD thermometer with an internal probe.

HTH.
 

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I have a 250W in my 90 gallon but I have even run a 200W with no problem maintaining 78 Degrees.
 

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Discussion Starter · #5 ·
A question for those with the 250w in a 90g tank.

What am I doing wrong?

I have a 250w Marineland Stealth placed on the side wall of my 90g and I can't get my tank to heat up past 60°. When I feel the side of my tank it seems warm in the area of the heater but a few inches away it starts cooling off. I tested my thermometer by running it under hot tap water and it rose to 80 in a few seconds, so I know it at least works.

Could there be something wrong with the heater?
 

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What you need to do is take your aquarium gallons and multiply by 5 and that is how many heater watts you need. For a 90 you need 450 watts.
 

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I have a 100w Stealth in a 55g. It will keep it 78 F without problem.

I did however notice that it takes forever to raise the temp. This is what I wanted though. During cycling I had a 250w heater malfunction. I came home and the tank was 90F!

I didn't want to chance that with fish. Some people use 2 watts per gallon. I'm now one of them.

Try to raise the temp to what you want it to be and then see if it can maintain it.
 

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gpaaib, My heater is the same as yours and I have it angled near the bottom center on the back wall and my thermometer is on the upper left front corner. I have a canister and two HOBs filtering the tank and maybe it has something to do with the water circulation in the tank. I can see the waves of heat coming off the heater when I look from the side of the tank. Stealth heaters are very dependable, but I suppose you could have a defective one. I rather doubt it though. I'm thinking it could be a water circulation issue. I've checked my temperature at various spots and it is uniform. Mine is at 80 degrees so I am amazed that yours is only 60. If you don't think it is due to water circulation then I would try to add another heater.
 

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horseman, the 5w per gallon rule is usually best applied to smaller tanks <75g. For tanks that are larger than 75g you can use a 2-3w per gallon as the standard. Reasoning being that large tanks are able to retain heat better due to their larger volume. See what happens when you put both a 5g bucket and a small cup of water outside in the cold or in the freezer. The small cup will freeze much faster than the 5g bucket. For a 90g a 250w heater should be just fine. It is important to keep it in an area with good water circulation and even better if you place it towards the bottom of the tank in a horizontal position

-MStatdfield
 

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I agree with the above. I have a 250W heater in my 180 gallon tank and I can keep my tank at 77F with no problem. Granted, it seems to be on more than off, but it keeps the temperature constant.
 

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shortround said:
I have a 100w Stealth in a 55g. It will keep it 78 F without problem.

I did however notice that it takes forever to raise the temp. This is what I wanted though. During cycling I had a 250w heater malfunction. I came home and the tank was 90F!

I didn't want to chance that with fish. Some people use 2 watts per gallon. I'm now one of them.

Try to raise the temp to what you want it to be and then see if it can maintain it.
:thumb: :thumb: :thumb:

punman said:
I agree with the above. I have a 250W heater in my 180 gallon tank and I can keep my tank at 77F with no problem. Granted, it seems to be on more than off, but it keeps the temperature constant.
:thumb: :thumb: :thumb:

5 watts per gallon is unecessary and risky. It'll cook your fish pretty quick if it malfunctions.

Here's a calculator. 1-2 watts per gallon is good for an acrylic tank.

All heaters have a differential. Meaning the difference between the temp when it first kicks on and the temp when it kicks off. It's usually about 1 degree. If you set for 80, then it may kick on at 79.5 and off at 80.5. If's ok if it takes a while to climb that differential. That also indicates it'd take a while to overheat the tank if it stuck on and kill your fish. You'll probably find that it also takes hours to drop that 1 degree. I know it sounds hard to believe, but get a heater with a light indicator and a digital thermometer and test. It'll prove it out.

The 3-5 watt recommendation comes from the heater manufacturers. Just like filter ratings from filter manufacturers, it shouldn't be take seriously. It's not real world.

Using multiple heaters without a controller may just result in only one heater ever coming on.

if a 250w heater doesn't heat a 90 gallon tank, then either the heater is faulty or it's not positioned properly or there's poor circulation in the tank. Place it horizontally with the heater element end near a filter intake.
 

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Discussion Starter · #12 ·
prov356 said:
if a 250w heater doesn't heat a 90 gallon tank, then either the heater is faulty or it's not positioned properly or there's poor circulation in the tank. Place it horizontally with the heater element end near a filter intake.
That could be my problem. At the moment I have it verticle on the opposite side of the tank by the output.
 

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gpaaib said:
prov356 said:
if a 250w heater doesn't heat a 90 gallon tank, then either the heater is faulty or it's not positioned properly or there's poor circulation in the tank. Place it horizontally with the heater element end near a filter intake.
That could be my problem. At the moment I have it verticle on the opposite side of the tank by the output.
The heat may then just be rising up past the internal controller portion of the heater and causing the heater to shut off. Laying it horizontally near the outflow should work too.
 

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gpaaib said:
A question for those with the 250w in a 90g tank.

What am I doing wrong?

I have a 250w Marineland Stealth placed on the side wall of my 90g and I can't get my tank to heat up past 60°. When I feel the side of my tank it seems warm in the area of the heater but a few inches away it starts cooling off. I tested my thermometer by running it under hot tap water and it rose to 80 in a few seconds, so I know it at least works.

Could there be something wrong with the heater?
What temperature is the room where the tank is located? Most heaters can only raise the temp 10 or so degrees from ambient.

You will get the best performance from your heater if you lay it horizontally and in an area of good water flow. If the water is not moving past the heater at a steady rate, the heater will heat just the water around it and when that very small pocket of water reaches temp, it will shut off. This problem is compounded by having the heater vertically. The taouto shutoff thermometer is located in the top of the unit. The heater warms the water directly surrounding the unit, it rises and triggers it to shut off.

I have had the best lick by putting my heaters at the bottom of the back (or side) wall with one of the filter outputs pointed directly at it. That will give you the best (and most even) heating for a tank.

If you need to, add a small powerhead and have it blow directly at your heater to move the warmed water off and allow colder water to take its place.
 

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I have a 250 watt on my 125 gallon and also on my 160 gallon. I put the heater in the middle of the tank by the waterflow. I have a thermometer on both sides of my tank and the water is a steady 80. I started with one heater on each side, then I took one out just to see if there was a difference. I didn't notice any difference so I left it out. I am keeping the other two as back up heaters for emergency. The aquarium heater does not run 24/7 and my home temp is around 70 24/7.
 

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I will buck the system. As long as the temp of the house doesn't drop below 70 degrees (some might even say lower than that :eek: ) you don't need a heater.

Burn me now, but you don't need them.

I have mbuna tanks that breed on a regular basis and show bright coloration. All are kept at room temp (70-72 in the winter/76-78 Summer). This mbuna need 80 degree F temp water is a falsehood. Yes they are less active, less agressive. I feed them less so they don't grow as fast, but they live just as long if not longer, the breed like rabits, and the coloration is outstanding. I have done both ways, room temp is the cheaper way (capital cost of heater purchase avoided and electrical cost per month reduced)

Ok, I am braced and ready for the bash...

(also, mbuna are not herbivors if they were you could let holding females release in a tank and they would all survive, you can mix feeding pelets and flake in the same feeding without getting bloat, you only need to dose a tank for the water changed even if you add water directly from the sink, you do not need 10x water movement for filtration, and more complex = not better! Sponge filters all the way baby!)
 

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Ok, I am braced and ready for the bash...
Thinking 'outside the box' lends itself to that, doesn't it? :lol: If it's worked for you, there's no arguing with that.

Only experience I've had is when a heater stopped working and the tank temp dropped to 75. Saw no difference in activity or behavior that'd tip me off.
So either it hadn't dropped far enough, hadn't been long enough or they'd do fine at 75. Hard to say and I'm not wanting to experiment, so I'll never know. :D
 

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Answer this:

Why do the divers in the rift lakes wear diving suits? Because they are comfortable or because the water is cold? When you are at a depth of 150 ft. (common for frontosa) is it really 75-77 degrees F like the forum profiles sugest they should be kept at?

I live in Texas so it never really gets cold, but we do get some cool weather. This is my first year doing so, but I know many that have done so with success. I am setting up a small above ground swimming pool and early April I will be moving fish out there.

Someone with experience told me that as long as the days get above 60 degrees, the fish survive just fine.
 
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