So I bought a automatic heater for my tank. It is a 2 gallon tank, and the heater will keep it at 78 degrees. I just read somewhere than you can not use a heater in less than 5 gallon tanks. It says on the package the heater is good for 2-10 gallons. Brand is Tetra. So I should be fine with this, correct? 78 degrees is a good temperature?
Tanks under 5 gallons can be heated perfectly fine with the right size of heater(generally 25 watts works well for smaller tanks, though depending on the brand you may be able to go up to 50 watts). Its tanks under 2 gallons that can be difficult to stably heat sometimes, and anything under 1 gallon generally can't be stably or properly heated.
So with the tank size, yes, you should be just fine. However, the Tetra brand heater you got is not a very good heater. They're notorious for under heating, most don't get above 75 degrees, and sometimes don't even work at all or stop working all together shortly after purchase.
I'd advise you to return that heater and pick up a different brand. What you'll want to look for in a heater is something fully submersible and adjustable with a thermostat. Hydor, Elite, Aqueon, and the Petco Brand are all pretty good brands.
I do believe Elites on Amazon are around $13 or so, if you don't mind ordering online.
Oh, and yes, 78 is a decent temp. But I find 79 or 80 is a good temp to keep your tank at....might only seem like a couple degrees, but it seems to make a slight difference IME.
choclate, it's not hard at all to heat an under 2 gallon tank. most adjustable 25w heaters will work. I've heated different tanks from .5 gallon to 2.5 gallons using 2 different 25w heaters and 1 50w heater. as long as it's an adjustable heater, it should not over heat.
I use the hagen elite brand on my two side tanks and a no name asian 25w heater in main tank.
If you try it, you will see that it is perfectly safe. Try things out first! lol
I used to be paranoid of heaters because when I was a newbie startin out everyone would say how a heater will cook their fish in a 1 gallon tank.
when I got around to getting my own adjustable heater, I was very careful, and tested it in a half gallon container. it kept te temperature spot on.
People spread false information all the time. it's good to be careful, and you should be careful with heaters and filters etc. but the majority of the time... they are perfectly safe and all the paranoia is unnecessary :)
I mean people say bettafix is bad... ALL the time. I've been seeing people around the forum using it without any problems for a while now.... so what is the truth about it? sure it may be a useless product, but is it really that unsafe, or are we all freaking out over a few cases that just happened the collide at the same time but don't necessarily have any true connections?
You got lucky then, I've heard of very few that actually work like they say they will. xD
I'd still suggest returning it. Tetras have a bad reputation of crapping out fairly quickly, even if you do manage to find one that works. Best to get a good, reliable heater that you know is going to last you a few years. ;)