Not if you let it dry! Make sure you use flat black paint (cheap stuff is
fine) and that it's throughly dry before you put it in the water. Give it a
day or so. Then, no problem. The paint will keep the new block from leaching
lime into the water, which would mess with your pH.

Lee
"Michael Shaffer" wrote in message
...
doesn't the paint contaminate the water?

Lee Brouillet wrote:
I took 4 concrete blocks and painted them black, then lined them up so
there
were tunnels that the fish could hide in. The side benefit: there's a
nice
platform on which to put stuff (plants, rock formations, trickle tower,
fountain, etc.)

Lee

"Michael Shaffer" wrote in message
...

hi, anybody know a good way to make a hiding area for some Koi? Would a
plastic crate be ok? We have a racoon here so I'm just worried about
them being eaten.