2-piece bottom pane questions

Backfromthedead · Mar 30, 2020

Hey MFKers,

Finishing up prepping the bottom panel on my new build. This is what i got so far:

Bottom panel is two pieces of 15mm, a 72x18 and a 72x30, joined with silicone at the seam.

My question is should i reinforce the seam or whole bottom panel? And if so, how? Ive heard that it should work fine as is but if i need reinforcement I'd rather do it now than later.

I have several pieces of glass to work with, and can cut them to fit if i need to, but unfortunately no pieces as long as the seam (71")

My best and easiest idea so far is to use a 60x30x12mm panel i already have to bridge the seam, then just seal all the outer edges with silicone. Would this even help?

Thanks for any and all help.

fishdance · Mar 31, 2020

You won't need to brace or reinforce the bottom pane as the stand base looks very solid. A 2 piece bottom is often preferred on long tanks as this handles flex better and is cheaper/easier to build. If you think about it, this joined bottom seam has the same strain as the join to side walls and you don't reinforce those.

If you do want to reinforce the base, I would run a brace around the walls to get a double bottom layer for better adhesion to the side panels. Not needed but that's the most beneficial. This brace doesn't need to cover the whole bottom but make sure you silicon each edge because algae /dirt will creep in and you won't be able to clean it out without stripping the glass off.

I have butt joined side wall panels as well as bases (without reinforcement strips) to create looooong loooong tanks. Removing end pieces and joining multiple tanks end to end to end.

Backfromthedead · Mar 31, 2020

fishdance said:
You won't need to brace or reinforce the bottom pane as the stand base looks very solid. A 2 piece bottom is often preferred on long tanks as this handles flex better and is cheaper/easier to build. If you think about it, this joined bottom seam has the same strain as the join to side walls and you don't reinforce those.

If you do want to reinforce the base, I would run a brace around the walls to get a double bottom layer for better adhesion to the side panels. Not needed but that's the most beneficial. This brace doesn't need to cover the whole bottom but make sure you silicon each edge because algae /dirt will creep in and you won't be able to clean it out without stripping the glass off.

I have butt joined side wall panels as well as bases (without reinforcement strips) to create looooong loooong tanks. Removing end pieces and joining multiple tanks end to end to end.

Appreciate the advice. The bottom brace is not a bad idea. I guess i would just omit the inner seals when building, lay in the brace pieces later, then seal the whole thing.

Tank will be 27" tall. What would you do to brace the top? I was considering glass corner braces, then additional middle vracing on the canopy if it needed it.

jjohnwm · Apr 4, 2020

Interesting thread. A question: at each end of the joint where the two bottom pieces meet, it seems that there will be a spot where the new silicone (attaching the upright end pieces) will be in contact with the old cured silicone that constitutes that long joint. How will that point be made waterproof?