i am actualy growing in soil for the moment. i like to mix up nutrients ahead of time so i am not constantly mixing and its always on hand. i have to use reverse osmosis water which litraly has no buffers. mixing nutrients and storing them is essentialy the same thing as having a resevoir. i am currently uning the organic line up from advanced nutrients. my initial reverse osmosis water has a ph of about 8.0. after adding nutes its at 5.o. i then add ph up to achieve 6.3 to 6.5. the problem i am having is that after a day it quickly rises to 7.8. i have to keep adding ph down to the nutrient mix each time i water. im thinking that there might be a buffer to help lock and stabalize the mix. what are you hydroponic users using to help stabalize ph in your resevoirs?
is there anything to help stabilize ph in resevoir
- Thread starter 711grower
- Start date
fatman7574
New Member
The simple way to look at hydroponics nutrients is to just consider that they have no buffering capacity. It is hard to buffer against a pH decline when there exist only a very few bicarbonates due to the low pH of the nutrient solution. Then the only real buffering aginst pH rise is Phosphorus. Phopsphorus is toxic to plants at large concentrations so little buffering is done by the limited amount of phosphorus. So unless your nutrients have a ratio of ammonium to nitrogen that is perfect for the temperature, humidity and lighting you provide pH changes will always be an issue. Even the bushiness, the amount of side lighting or refective side lighting your plants receive will alter the amount of ammoninium taken up by your plants and therefore effect your pH. Just ignore the people like Earl or Uncle Ben who say you can add extra bicarbonates/carbonates or properly balance your pH and avoid pH rises and declines. It simply just does not work that way.
fatman7574
New Member
That or buy a pH controller. There is a normally retailed Omega pH controller on ebay now you could probably get for $50. It uses a standard pH probe with a BN connector. Just gravity feed through to cheap plastic solenoid valves from ebay. The controller is very very accurate and has many safe guards built in to prevent over dosing your pH up or pH down solutions.
http://cgi.ebay.com/Omega-PHCN-37-Microprocessor-based-pH-Controller_W0QQitemZ190382865101QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2c53b3facd
pH probe:
http://cgi.ebay.com/PH-Probe-for-aquarium-PH-controller-Meter_W0QQitemZ250591881013QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a5870a735
Solenoid valves:
http://cgi.ebay.com/1-4-Plastic-120VAC-Electric-Solenoid-Valve-Water-Air_W0QQitemZ140385904352QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item20afa6e6e0