Here is the answer to how much to use I use half a tablet in a 23ltr brew any more and it becomes like soup and you can get a load of extra trub.
Protafloc is used at a lower dosage as it is more efficient. The dose is around 0.3 – 0.5 milligrams per litre or 0.75 grams for a 25 litre batch. Tablets are made in 2 gram sizes so just under half a tablet is fine. Add directly to the wort 10 – 15 minutes before the end of the boil.
Hmm, that's interesting.. I normally use a full tablet and don't think much of it, but this week I brewed up a golden ale, about 26L left post boil and set off the whirlpool as normal. Hops put into a hop stand.. after standing for a bit, then chilling, removing the wort chiller/hopstand and then whirlpooling for a few more minutes and letting it settle, it was really murky/hazy (soup like as you will)..
I actually put it down to this being my first 30minute boil (although I did boil it harder than i usually would) as my first hop addition was at 15mins so i figured a good brew to actually see what the fuss is all about these 30min boil times..
I might consider my protofloc regime then on the next brew and see if my soupiness changes as i was expecting this particular batch to be a lot clearer than what it looked like in the kettle.