What's the Temperature?

[Mr. Breeze]

I have purchased an Aqueon Evolve 8. They sat it's an 8 gallon, but it strikes me more as a 5 gallon. I bought a 25 watt heater that is preset and looks like it is working, hence the red light turning on and off. I also have good water circulation.

My issue is that the tank looks like it is staying at 74 degrees. I have a stick-on temperature gauge. Me questions are:

Does acrylic material distort accurate readings?
Is 25 watts enough here?
Should I check the water directly with a different thermometer?
How much variance is there with these smaller heaters?

Any ideas out there, especially those of you with smaller nano type set-ups.

Thanks,

Mr. Breeze

 

[librarygirl]

I like the in-take mercury thermometers better, I think they're more accurate (well, easier to read at least) then the stick-ons. Some pre-set heaters are only set to 75, others set to 78. See what the package says. Many heaters can be off by 1-2 degrees either way. Every preset heater I've tried dies in a short time; I prefer the adjustable ones.