Yes the 140 will exhaust quickly, if it were me using your chems, I'd run 1 roll in the first 140 and then only keep 90-100 of the used solution and add 40-50 ml of fresh to get back to 140 for the next roll.

I always use distilled water for mixing chemicals, it's just one less variable, I do wash in tap water but the film is always finished in stabilizer that was made with distilled water.