Back plumbing - Stress on glass?

[Scuba_Dave]

How often does everyone shut their valves?
I've yet to really have to turn mine off.When I clean my sump, I clean my pump.
So the sump/pump ball valve is the only one I really "need". Everything else I let drain down to the sump

I have:
(5) 1.5" valves
(9) 1.0" valves
(3) 3/4" valves

plus spares of all
(2) 1.5"
(2) 1.0"
(2) 3/4"

True 1.5" are close to $25 each...that's $175 for stuff that is rarely used...?
Just for the 1.5" !!

You weak wristed guys need to work out more!!
They are a pain tho....

 

[Yaktop]

the longer you dont use them the harder they will be to close or open. I'm using the HD's for the drains but true unions for everything else.