wet plate fixer question

moderators please move this if it isn't in the right place, i wasn't sure where to put it ...

hi wet platers

im not a wet plateer ( yet ) and i had a question for folks who are doing it now and might be able to help me.
this isn't really my question but as you know i sell silver recovery stuff and someone emailed me a question i couldn't answer. people usually email me regarding KCn and the manufacturer of these devices says that they won't work with that sort of fixer .. but i recently got an email from someone who uses plain old hypo and i wasn't sure what to say.
for his fix he uses sodium thiosulphate mixed with water as a fixer,
the collodion formula is with potassium iodide and potassium bromide,
and a iron(II)sulphate developer So... the silver on the plate is in the form of silver iodide.

is the waste in the fixer pretty much the same waste that is in there when making a paper or film (modern) print/negative?
with a trickle tank the target ph has to be about 5-6, does this change when using silver suspended in collodion?

thanks !
john