400 gallon tank

[spencer0t]

Are you doing glass, or acrylic?

Is acrylic expensive is so then I'll do glass I don't know what type though

 

[DarylMac]

If he plans to drill the tank then not tempered or else it will shatter

Of course. I have an empty 75g in my garage that has a tempered bottom panel. I believe that is, or was, industry standard, except on "reef ready" tanks.

 

[BIG-G]

I don't know what type though

Glass is either Tempered or standard plate glass or you could get starfire glass which is a trade name for just low iron plate glass, it looks clear instead of green. When you get thicker size glass it will start to look kind of greenish thats why people use starfire.
You cant cut or drill tempered and if tempered glass ever breaks it explodes into tiny pieces.
Plate can be cut and drilled but its not as strong as tempered.
I hope that helps you understand what everyone is saying about glass choices.