should i un pot a wendtii plug?

Yes, take it out of the pot and rinse all of the wooly material off of it.

Don't be surprised or alarmed if the plant looks like it's going to melt away. It will grow back and is common for crypts.
 
Oddly enough none of the dozen or so crypts I have ever melted even though I was expecting them to. Now getting to the original question yes unpot, rinse, and plant in the substrate.
 
My bronze wendtii did it after months of having it in really bad conditions. I put it in the 55g...within a month it melted to nothing but grew back nicely. None of my others did though...

Ok, sorry to butt in with that.
 
It'll just be messy. I usually swish the roots around in a bucket of water to get as much of as I can, after I've pulled the big chucks off.
 
rock wool and fertilizers

You need to get as much of that rock wool off as possible. Use tweezers. It is saturated with fertilizers and is likely to lead to algae problems in the tank if you don't remove it.

Also, when you plant the plantlets, trim the roots if necessary to about 2 or 3 inches whatever looks right with the size of the plant, push it down in the gravel and then pull it back up so that the roots are showing just a tiy bit.
 
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