55 gal tank Question

I have a 55 gal tank that was freshwater that i switched to saltwater 9 months ago.
I read that a freshwater tank is thinner tempered glass and may not stand up to the weight of the saltwater, live sand, live rock and could give way.
should i be worried? it's been o.k for 9 months.
I found this in my area 75 gallon Aquarium saltwater setup
Is this a good deal?
are there any questions i should ask the seller first?

 

First, unless the tank was meant for reptiles, the glass thickness will be the same whether its for fresh or salt. No difference there. However, if you can upgrade to a 75 or 90, do it! A 55 is just too narrow.

That specific tank you listed is an ok deal. Nothing great though without seeing it. I picked up a 125 tank, stand, lighting, sump, return pump & UV for $300. Plenty of others have even gotten better deals. Just be patient if you can!

 

That sounds like a pretty good deal.

I agree with Marshall on the strength question. I have never heard of there being any difference between salt and fresh water aquariums. I wouldn't worry about the strength so long as the frames are all solid.