Temp Fluctuating Too Much?

I set up my new 70L tank at the weekend. By set up I simply mean substrate in, water in, heater, light & pump in and let's see if it springs leaks. It shouldn't but just in case.

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70Litres = 15.40 Imperial Gallon = 18.50 US Liquid Gallon (i'm not sure what the tanks are measured in when people refer to gallons).

Now the thermometer possibly isn't the most accurate but I was expecting the reading to be consistent. I set the heater at 25c and the thermometer read 25c. Great stuff I thought. By the time I woke up it was 23.7c.

I've had a bit of a switch around. Put the heater on the back wall in the middle of the tank. Turned the heater so that it's sort of between 25c & 27c (strange that they go up in odd numbers?).

The thermometer appears to go between 24.3c-24.6c which is a shorter range than it was doing at the start of 24c-25c. 1 degree is quite a jump for small fish, no?

Question i'm wondering is is this fluctuation part of setting a new tank up? And is it now at an acceptable range of fluctuation?

The heater looks like a SuperFish Eco Heater 100W. I'm wondering what you guys would suggest here. A big brand singular tube glass heater? 2 heaters at either end of the tank maybe? What size heater?

As you can probably tell i'm a bit of a newbie to this so advice welcome.

 

I set up my new 70L tank at the weekend. By set up I simply mean substrate in, water in, heater, light & pump in and let's see if it springs leaks. It shouldn't but just in case.

.
70Litres = 15.40 Imperial Gallon = 18.50 US Liquid Gallon (i'm not sure what the tanks are measured in when people refer to gallons).

Now the thermometer possibly isn't the most accurate but I was expecting the reading to be consistent. I set the heater at 25c and the thermometer read 25c. Great stuff I thought. By the time I woke up it was 23.7c.

I've had a bit of a switch around. Put the heater on the back wall in the middle of the tank. Turned the heater so that it's sort of between 25c & 27c (strange that they go up in odd numbers?).

The thermometer appears to go between 24.3c-24.6c which is a shorter range than it was doing at the start of 24c-25c. 1 degree is quite a jump for small fish, no?

Question i'm wondering is is this fluctuation part of setting a new tank up? And is it now at an acceptable range of fluctuation?

The heater looks like a SuperFish Eco Heater 100W. I'm wondering what you guys would suggest here. A big brand singular tube glass heater? 2 heaters at either end of the tank maybe? What size heater?

As you can probably tell i'm a bit of a newbie to this so advice welcome.

How many watts is the heater?
I have had lots of heater problems before, in fact I just bought a new one today.

 

I would add another 100 watt heater. I recommend 10 watts per gallon for tanks in colder rooms and you are at about half that.

 

I would add another 100 watt heater. I recommend 10 watts per gallon for tanks in colder rooms and you are at about half that.

That seems like way too much. I have a 65 degree room, and my brand new Aqueon 100 watt adjustable heater (set to 78-79 degrees) is doing a great job in my 20 gal (so far).

 

That seems like way too much. I have a 65 degree room, and my brand new Aqueon 100 watt adjustable heater (set to 78-79 degrees) is doing a great job in my 20 gal (so far).

Aquarium heat is a case by case basis. Water volume, water circulation, tank location in the room, type of lid, exposure to sunlight all play a role.

Some have great success with 3-5 watts per gallon. The OP has not. I haven't either

 

Or it could be a problem with the heater.

 

Could be, could also be the tolerance of the thermostat.

Seeing as his tank is colder in the morning it sounds like his home gets colder at night and his heater is slightly undersized.

My 10 watts per gallon rule saved my 11 fish when my heat went out and my house was 50 degrees.

 

I know even new electricals can have faults but just to say - the heater is new. With that said, I don't think it's a fancy one.

A couple of links to the heater would be Amazon & ProShrimp.£11-£15 for 100W seems quite cheap so I don't think it's one of the market leading ones. My wife bought Aqua One heaters for the Betta tanks and i'm sure they were getting on £20 for 55W or thereabouts.

So 2 questions for you really:

1) What watt heater would you buy for a second heater? Stick with 100W for this size tank (70 litres)?

2) What heater (as in brand/model) would you buy? I don't know what's a respectable name in this market as i'm new to it.


Oh and for further info: I went to bed last night & the temp said 24.4c. I woke up & it said 24.3c. Came home from work & it was 24.2c. Just ate my dinner, came back upstairs & it's 24.4c.

Like I said, I don't know how accurate it is so for all I know it could really be 26c or 22c which is why when I change water I use the same probe thermometer - probe the tank & then probe the new water to go in the tank so that while it may not be 100% accurate it'll at least be consistent.

 

The best thing to do is to watch the tank for a few days. One degree C difference is not a big deal. If it bothers you add another 100 watt heater for a total of 200 watts, a little over 10 watts per gallon. With 200 watts in that tank you will see temperature change of less than a degree.

I like aqueon pro heaters. They are not expensive, adjustable, and have a lifetime warranty.

 

Heater location has a lot to do with it to. If its were it doesn't get flow the heat will not dissipate into the tank it just stays by the heater.

 

I did have the heater on the side with the pump pumping in to it but now it's in the centre at the rear of the tank. It actually made little difference as the pump seems to push the water around well enough.

I also wonder what to believe regards the temperature. For example...




^^ That is the setting on this heater....




And this is what it produces...




Those are just cheap thermometers off eBay but it shows the problem.

I don't actually know what the temp is in the tank. I'm sure it's somewhere around that but how accurate they are I don't know. For consistency when I do water changes I use the probe that i'm holding in that photo & take the temp of the tank and then use that same probe to get the new water to the right temp so that it's the same.

I was wondering about this heater...




Good heater? From what i've read it's supposed to be. Would you go for 2x 100w for a tank this size?

Thanks.

 

The numbers on the little dial aren't always accurate. I just start there and adjust the dial as needed.