I've been getting pretty impatient waiting for my waterfall tank to cure. I've had it sitting in water in my shower for the last three weeks now, but it's still around 8.0 pH. That's not super high, but it should probably be down to 7.5.
I decided to make the background for the second tank I bought, but this time, I didn't want to wait for it to cure.
painted it with concreted like normal. But then I went and purchased
some pond paint made specifically for concrete koi ponds. The can says
(I'll post pics later) that it stops all leaching of alkaline into the
water. I don't think that it necessarily waterproofs it though. I'm
going to do a couple coats of this, and then put a layer of epoxy. I'm
thinking that should make it pretty safe, and then I can use it straight
The color of this stuff is pretty bad--it's
that light green color. I thought I would just paint over it once it
had dried, but I decided to just add some acrylic paint directly into it
and it changed to a nice gray. One more coat and it should be pretty
good. I'll paint some highlights in and then I can add the epoxy. It
should be finished in just a couple more days.