So I’ve been brewing with my converted round 10gal cooler for 6yrs now but lately I’ve noticed where my false bottom has scratched the sides of the cooler. Didn’t think anything of it till last brew I had a really bad back of tongue astringency that just wouldn’t go away even a month in the keg. initially thought it hop burn or creep so changed my process this time, wp at lower temp with less hops, fermenting cooler mid 60’s but let it free rise to 73 for diacety rest and tonight I took a gravity sample at day 9 and the sample had that same back tongue astringency and this is before the second dh. So when I cleaned my tun last batch I pushed on the bubbled area in my mlt and stanky ass wort came out of a now breach in where the plastic is scratched. I’m wondering if this is doing something with the mash causing this off flavor even after I boil thinking that would kill any bug that may be in the scratches in my mlt.