Leaving Empty Aquariums Outside

No, should not be a problem. Tanks sit in stores for a long time too.
 
Haha I'm glad I saw this. I resealed a 55g a week ago and after testing and emptying it it is still outside. I started to worry for a bit and was going to make this same topic but then I realized the same silicone is used on windows so if the heat won't mess with that I should be good XD
 
I would be more worried about silicone (1) drying out and (2) being exposed to too much radiation (infrared and ultraviolet) from sunlight. Windows are not designed to hold water.

If you can keep them in a shaded place constantly that would be good. Even better, keep them shaded and fill them with water, and maybe with a light-colored tarp over them, both to keep out dirt and reflect off potential problems from sun. If we're only taking a few days or weeks, don't bother, but if there's a chance they might be exposed for a longer time, water and tarps are cheap.
 
As XanAvaloni mentioned, it's not the heat that can damage the silicon, it's the UV rays from the sun.

I also agree that a few days (week or so) shouldn't affect it. A tarp as suggested would be good just as a precaution if you have one. I wouldn't go buy one just for that though if you think someone will be getting it soon.

I was given a 10 gallon that had been outside for almost a year. But it was against the house that had a little overhang from the roof and was never directly in the sun. The silicon was discolored but it holds water just fine. Though I would not recommend leaving/storing a tank for that long outside.

Oh, but if you get a taker/buyer, rinse the tank off and dry it before they get there to make it look purty :)
 
If you keep it in the shade, it should be fine. If it's going to be for extended periods, cover it with a tarp. Silicone does dry up with the elements and becomes brittle. Weeks shouldn't be a problem, but months...eh, I wouldn't!
 
I got a tank from a friend who'd left it outside for months (possibly even longer), including during a rather nasty storm that blew down trees on a couple of the other tanks left outside. It holds water just fine.
 
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