I actually published an article on this very subject many years ago.
this is a direct quote from my article I published and it should clear up any confusion on this..
"The origin of this myth most likely has to do with the rust colored oxidized metabolites of trenbolone which are excreted in urine and often mistaken for blood.. Trenbolone and 17epi-trenbolone are both excreted in urine as conjugates that can be hydrolyzed with beta-glucuronidase.This implies that trenbolone leaves the body as beta-glucuronides or sulfates."
and yes drinking water helps, its like shitting in a toilet and then leaving it there.. the water will turn darker right? when you flush it then it clears up.. this is the same concept. so if you drank more water the problem would lessen. and then you got the tren pumps in the lower back, which people think is kidney related.. oops. now you see why people get scared and go to the doctor in this situation
there are a few items that are must runs on tren and its not even up for debate.
1. GW - this will counter act the negative endurance issues
2. n2guard- this will help cleanse you .. obviously OP you aren't using it, when you run n2guard you will notice this issue lessens
3. a quality PRE/PRO biotic like sach boulardii.. please don't buy dairy based pro biotics, they are a scam
4. immune system booster.. you can either run primo with it, LGD, or get some colloidal silver
if you do those things your experience with tren will be far superior