custom tank?
 

hey wondering if anyone knows how much a custom tank would cost, something 3ftx2ftx18" or something around there

Call King Ed's or OA or J&L.

do you have any idea on how much they go for?

He probably doesn't, that why he said call the stores. Custom can be expensive though, depending on how "custom".

thickness of the glass, overflows, drilling, bracing, glass type, etc. There's far too many options to say it's going to cost x.

what thickness of glass would you say i needed for a 60 gallon roughly 3ftx20"x20? and im thinking of going external overflow and rimless

If you're just budgeting my price would be roughly $500 for standard 10mm glass euro braced with no black trim.
Extra charges are roughly as follows:
Internal Overflow: $75
External Overflow (notched glass): $150
Dual Drain: add $25
Holes for return or CL: $25 per hole.
Starphire Front: add $60 (three sides $100)
Polished Edges (standard dual chamfer): add $200

Not sure how these prices compare to places in your area but hopefully it helps, glass prices in Saskatchewan are significantly higher than Alberta and BC. These are also just rough estimates for budgeting purposes only.

yah i ws thinking around the same thing, pretty expensive but it will look unreal when its done