Digital BW, The Print

Shame of all shames! You were right on, Paul. Although my carts were not 
empty when I last used them, now they are! I feel like those clients who 
used to call me for a computer problem when it was simply unplugged...

Does this mean that carts just empty themselves over time? A combination 
of leaking and evaporation?

Anyway, I now have a new task at hand: cleaning the carts and flushing 
the ducts and heads. Having gathered info from old posts, here is what I 
plan to do, please correct me if there is a better way to proceed:

1- rinse carts with distilled water (necessary?)
2- rinse carts with flushing liquid, possibly using ultrasound to loosen 
old ink
3- empty carts
4- fill carts with flushing liquid and do head cleansing cycles
5- empty carts and refill with ink

Questions:
How do I mix flushing liquid, I have:
- clear base b (with Edwal)
- ammonia
- isopropyl alcohol

Are all of these mixable? Should I avoid Photoflo and Edwal to get in 
contact with ammonia and/or alcohol and thus preferably start from water 
and glycerol?
What proportions?

Thanks for your kind help
Louis