That is exactly what it is. I have been battling it in my tank for some time.
This stuff can feed off of small amounts of nutrients, so that is a big part of a long battle.
I've run gfo
, skimmer, and just recently bio pellets. It wasn't until I got the pellets going did I even start to make a dent in the stuff.
Pull the stuff out during water changes. This stuff burrows into the rocks, so it will be hard to pull out if there are nutrients to feed off of. When they get low, it gets very easy to pull out.
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