I tumble Phosguard.
Both work equally well.
clumps, making it unusable for tumbling in a high calcium tank after a few weeks. I've tried all brands and grain size.
It's messy, stains everything.
Phosguard color changes to give you an estimate as to when to change it. It turns a light chocolate brown.
Phosguard tumbles easier and doesn't clump as bad IMO
Some say the aluminum in Phosguard is unhealthy, I have seen no sign of that.
Just a few observations.
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