Yeah it's all starting to look pretty good now I've made some adjustments. Just a few more trivial questions before I get on with it:
1) I'm not using a pre wash. Will the accumulation of the anti halation dye from the paper into the developer have any negative effects on the developer? Could it stain my paper or does it have no effect?
I never noticed a problem with this despite never using a prewash and having used the same batch of replenished developer for over a year (hence it's pretty much saturated with muck).
2) I store my chemicals in my laundry room overnight and the temperature is about 16°c but by the end of the day they are about 20°c. Will this change in temperature cause inconsistencies in colour balance or does out make no difference at such low temperatures
Again, I never noted problems with this. I wouldn't let the stuff cool down too much in order to prevent anything from precipitating out, which will likely not be much of an issue anyway with a working stock. Anything above 10C should probably be just fine.
3) Before my blix I'm using a stop bath then wash. I assume that over time the wash carryover will dilute the blix. I'm already replenishing at 15ml per 8x10. Will this be sufficient or should I bump up !y replenishment rate?
I replenish my blix way less and don't use a wash between stop and blix, and my blix still blixes like any blix that has ever blixed before. Or, better put: as long as you replenish according to the manufacturer's spec, I wouldn't worry about it. Blix is tremendously overdimensioned, or put differently, its usage instructions are insanely conservative.