[Sk8r]

I had a 5' long acrylic tank with a top brace, big acrylic sump with no top-bracing.

Ran it nearly 10 years. Over time, the top stayed pretty steady---but the bottom [unbraced] developed an increasingly alarming bow outward. Warm water and weight bends plastic, nuff said.

I have also had a 6' TALL triangular tank turn loose its back-seam under warm water and pressure. THAT was an expensive mess and a disappointment.

I have had a rockslide put a permanent deep scratch on my tank face.

And after 10 years, the top brace was showing stress, meaning warm water, exposure to strong lights, over all, was proving that plastic is more reactive than glass to both those pressures.

So, no, the joy of using a razor blade on a coralline encrustation, the surety that my very thick glass will NOT bow under the ordinary pressures of my tank...I use an acrylic 30 g sump [bowing already!] and will continue to use acrylic in sumps and other places where drilling is necessary----but for view and long-term stability, give me glass, thank you.