lime doseage

How much lime to bring a ph of 4.5 up to 6.5 is recomended?
I am using 10 ltr coco and i just flushed one pot with 100 ltrs tap water which only brought it up to 5.5 ph .

1 tablespoon per gallon, is what alot of guys use, and I've used it myself with good results. I'd go with 3 gallons(12 liters) first, then check and see what the PH is. That should bring it up quite a bit, but 4.5 is pretty low so you might have to use more than that. I guess you'll just have to monitor as you flush, and stop when you get to what you're shooting for.

Also, if you happen to go up over 6.5,(not real likely) don't freak out because the PH will come back down soon enough. Plus, the lime should hold your PH where you want it for awhile, although you may have to add some more sometime down the road.

Too much can be brought into growing a simple plant make sure that the ph of the feed that you are useing is right and belive me if you buy a decent soil base like bio bizz the plants will be fine in all my years of been around cannabis i have never ph'ed my soil.The main thing is the nutrients that are going into the soil is ph'ed right it will all fall into place.