WOW PEOPLE just give the guy a strait answer
listen to me if your in a soil or soilless mix then your pH needs to be 6.2-6.8 going in and coming out after doing a flush. If your tap water is to high get
pH down if its to low get
pH up and make it right before using.
BTW You use 2 times the amount of water that your pot holds for example
3 gallon pot = 6 gallons of water for flushing this water needs to be about 6.5 going in from the top of the soil and when your done it will be 6.5 coming out if its not dump more water in it make sure this water sits 4 at least 24 hours b4 you use it. After you are done follow up with 1/4-1/2 strength nutes id say 1/2 gallon for a 3 gallon pot then let it dry really well before you water again all water must be 6.5 going in and
nutes will lower water and soil pH so be careful hope this helps

+rep would be nice thanks