I keep it in a 32 gallon rubbermaid with a marineland 800 circulating. I did a water change last weekend, then filled it back up with RODI. I didn't add any salt, but kept the circulation running. The pump was about half-way down the side of the can aimed lazily down. I was going to add salt today and just noticed a really weird looking green type substance on the bottom of the tank. I lowered the pump and it blew some of it away and it kind of flaked off and then some of it went up kind of like sand. What's going on with this? Is this water still any good?

P.S. Reading through this thread is really depressing...

Thanks,

brando