How? If it's iron and/or manganese being metabolized by bacteria and the bacteria is in your lines, what do you want them to do? Don't put any iron or manganese in their salt?it’s dirty period fix it..
Your tank water may be depleted or super low on iron/manganese. Thus, it's not being metabolized in the lines.
Just throwing this out there. If TM can't find the problem, what do they fix? If you literally can not find the problem with a car, do you just "fix it period?"
FWIW, I've never seen a single salt keep things perfectly clean long term. This includes ESV which is even cleaner than TM Pro.
I've been using TMP for about 2 years. Four empty 200 gallon buckets that was great salt zero complaints. My last bucket mixed dirty (like everyone is complaining about) I was concerned about it hurting the tank. I called Tropic Martin and they ensured me it's completely safe. About 4 months on this bucket and my tank was starting to crash. I lost SPS, tons of euphyilla, blastos, favia, and more. I was going crazy doing everything I could think of. A last resort I stopped by Petco on my way home from work grabbed a bag of IO made a water change in the same mixing station I've been using. Water change the next day and within 24 hours my tank looked better then it had in a month! Also my mixing station was cleaner with IO then TPM! The rest of that bucket went right in the garbage and I'm trying to sell my other two new sealed buckets. I'll never touch the stuff again.
So, you know the salt is a problem and your answer it to sell it to some other hobbyist?