White mold in s/h

[Ray]

You also have to remember that there are soluble residues in the medium from the manufacturing process.

[Ross]

Originally Posted by Ray

You also have to remember that there are soluble residues in the medium from the manufacturing process.

Didn't we have this discussion a while back

For what it's worth, I get the same "cobwebby" deposit on gravel in my drip trays from the MSU solution. I agree with the salts buildup.

[quiltergal]

I give my s/h pots a double flush with plain water before the final water with MSU every week. I know it takes longer to water that way, but I'm not seeing any salt build up or mold. Algae is another story.