Temperature drop at night?

I have a 60g open top tank that is in my room, at night the temp in the tank drops to about 73 while it is usually 77-78, I have no livestock right now as I am cycling but would a drop in temperature like this harm future fish and coral?

 

That is too large of a temp swing to have daily for corals and fish.
Sounds like you just need to put in a heater or two and you will be all set.

 

How big of a heater do you use? I would use at least a 250w heater and set it to 77. This way, it would only drop 1 degree at the most. Heater will kick in as soon as the temp drops to bring it back to the set 77 f. If you can keep the water stable at 78, even better. Not that temps at 77 are better than temps at 78, it's only that the temp stability is a good thing. I have 2 heaters in my sump, both set to the same temp. If one goes out, the next one will keep up with the temp.

 

I have a 250w heater, in the morning when the tank was 73 the heater had a green light saying the temp was at 78 when it wasn't so I had to play with the dial just to get it to start heating. I am going to purchase an acrylic canopy to help keep heat in.

 

If you have a sump or an alternate mean to oxygenate the water, I'd say go ahead. Otherwise covering the tank will bring down your oxygen level greatly.

My heaters do heat the water to 78 when I set the dial to 78. Something may be wrong with it. I know those heaters with the green/red lighted dial, Marineland is a good brand and that is what I use as well, only these are the older models without the color changing dial. Test it out, since this is the right time to do so. If something is off, you may want to talk to the manufacturer. Hope you kept the box!

 

I have had the heater for a long time and it has always worked, yes I have a large fuge that I will run opposite to my tank and I could add an airstone in there. I think I will leave the heater in there and and also run a seperate heater (250w Jager) in the sump.

 

I wouldn't trust a heater that reads the water temperature wrong by that much. It could end up killing your fish overnight which is a fairly common thing to happen with heaters as they get older. Just because it has worked for a long time doesn't mean it is something to be trusted, it just makes them much less dependable and much more dangerous by being old.

 

Good point, I will try my other heater and see how it goes.

 

+1
agree 100%, sounds like your heater is defective! I would use another and IMO, don't go cheap on heaters, I bought a cheapy back in my FW days and woke up to 92 degrees and 5 dead fish... I would also buy a heater bigger then what you need so the heater doesn't have to run for hours to keep up with the temp.. Currently I'm pushing about 160 gal of water( tank+ sump) and I have 2 heaters in the sump, both rated at 90 gal a pop and they have to run almost 24/7 here in the winter( las Vegas) to keep my temp at 78. So spend the xtra $$$ for quality and wattage... GL

 

I have a eheim Jager 250w, is that a good brand?