Also I do need to get a test kit I’ve alway sent it on that aspect just stayed on top of water changes and made sure to keep tank tidy I was in the hobby for about 2-3 years got Out and now getting back in I couldn’t stay away lol first time I’ve had so,etching like this happen in my tanksCurly whiskers on catfish is 99% always a water quality issue.
How long has the tank been set up?
What are the water parameters?
What volume of water, what occupants?
Water changes at 30% per week seems fine, assuming with dechlorinated water of similar temperature. And again assuming you vac tank gravel(it does look tidy in the photos).