my aquarium pH down by API is sulfuric acid. it contains no phosphates. the product specs say that it can be used on live plants. check out the manufacturers website and read the MSDS or product specifications. sounds like it will work.

on the other hand you can get something made specifically for plants. general hydroponics pH down uses food grade phosphoric acid.

ditch the probe meter. get a pH test pen. they can be found on ebay for ~$25.


-shake
headshake Reviewed by headshake on . My PH took off and I need to adjust radically Team, My PH is over 7 approaching 8 in my outdoor soil grow. Thanks to the hints here I was able to detect and now I know why some of my ladies are yellowing. I used some vinegar as directed yet the soil is still over 7 as measured with a low end probe meter. I used my pool chemical tester to determine my tap water is near 8.0 PH and verified with probe measurement so I know where the problem arose. Are there any long lasting PH soil adjuster you recommend other than vinegar similiar Rating: 5