Hi Rick,

String algae is what we usually call it.

But you should be able to grab it. It will hold together. It stays in one place
and won't float up and down. Sounds like what you have in your waterfall.
Some folks have had good luck with plain kitty litter. There is a link in my
sig site that talks about it. Also String Algae Buster.
Koi will eventually eat any snails you put in. Some snails carry disease they
pick up from bird waste deposited in the pond.

The mushy stuff is probably dead algae and you need to skim it out.


kathy :-)
algae primer
http://hometown.aol.com/ka30p/myhomepage/garden.html