I HATE CONCRETE
I made these rather cool rock structures, using dry rock, held together by concrete.
This week, another structure collapsed. Fortunately, no fancy corals on it, but
still a big hassle.
Not sure what the deal is, but the concrete has been slowly disintegrating in my tank.
A few years back a different one collapsed.
Most people have no issues, although some web searching has turned up a couple of others.
One theory was that using too much Acryl 60 polymer might be the issue, although I thought I
followed instructions carefully. No idea.
Oh well. On the plus side, I can do some new aquascaping!!
This time, I am using epoxy!
Real West System Epoxy, not that crumbly pink stuff with clay in it from the LFS.
I have some structures built with that, and they are doing great.