I'm trying to find a local store that carries ph up and down. I called English Gardesn ( a local gardneing shop) and he told me to get lime and sulfer. He said he carried the liquid bottles for ponds and stuff. When I asked him if that would work for growing plants in soil he said no. Is this true? and where/what can I buy locallyl to raise and lower the ph of my water for a good grow.