during first stage of a/b.
(specifically filtering acidic heat bath washes before reducing)
keep or discard?

keep every thing until you get your results and if something is missing you can go back and most likely find it.

Good Luck

Anyone know the max temp a solution should get when reducing?
p.s. the foam turned into liquid eventually.

Just below a hard boil of as a chef would low rolling boil, or simmer.

To calculate the exact temp I would need to know atmosopheric(sp) preasure present in your location. But no need to be exact. The higher the temp the faster the reduction. crock pot on low is great.

gracias MV. someone I met is reducing a dye solution in an oven and was worried about hurting it. someone in the chat even said it's possible to microwave it! my friends friend doesn't have a microwave or a crock pot.