5g's should be fine. I have 2 tanks a 150 and a 180 that have acrylic top braces. The Pressure on those is WAY more then you'll probably see. I've heard LOTS of people tell me it won't work, however NONE of them can show me a failure when it was done correctly. Silicone bonds to glass in the same manner it bonds to acrylic. I'm fairly postive on a chemical level there is NO chemical bonding between silicone and glass. So from a surface point of view, what's the difference between acrylic and glass? Both smooth non-porus surfaces. While a weldon bond MAY be stronger in certain instances, it doesn't mean silicone doesn't work.
Well, I have made external overflows for a couple of my tanks out of glass and the silicone is still going strong. I tried to glue an acrylic strip with teeth cut into it over the slot I cut for the overflow and it wouldn't hold. I know in my limited experience it wouldn't hold.
im gunna give it a shot, i have all the materials so it would be a waist to NOT do it.
and heres another part to the story. im in highschool and one of my classes is woodshop, and as long as you keep busy you get a good grade. i have access to all the tools and clamps i need for free, and i would be getting a good grade to do it. sounds good to me
I tried to drill my 2.5, i have drilled over 50 tanks so far with no breaks, but they have been all 10g+. The 5g and 2.5g uses the same size glass. I found it is possible to drill a 2.5 and 5, but what you need to do is drill almost all the way through, stopping just before you push through, then get out a dremel with diamon bit and finish the job, went through 3 tanks like that. One tank I just took the back glass out, drilled a piece of acylic, siliconed it all back together, and its now running as a nano reef with no leaks or bows, so it is possible to do that also.