Water ph changing at different temperatures

I had a suspicion that my ph meter was going off frequently, so I bought another one. Im very particular and I like for things to work like people claim. So when my second one came in, I tested it against the 7.0 ph buffer solution and tap water. I did the same test with my older ph pen also .... The readings where different, so one of the 2 was wrong. So just out of curiosity, I decided to by an aquarium ph test kit and use it to test with the other 2. They all read different. Before you call me a dummy, I knew that ph in water changed with temperature changes. I just did not know how much and how fast. I had dropped from 6.8 to 6.0 in 5 minutes .... So when I used all the meters at the same time withe same water at the same temp.... I got the same reading on all ph meters. Lesson learned, and Im to damned obsessed lol. Here is some reading to back this up... http://www.chemguide.co.uk/physical/...seeqia/kw.htmlSo it would probably be good to adjust your waters ph at the same temp as your grow room

A great discovery. Alot of ph testors are availible that adjust automatically to read properly at whatever the temperature is. It's not new info, but impressive you figured that out without knowing it from somewhere else. They make PPM meters that adjust to read accurately at different temps as well... +rep to you.

But doesnt it make sense to adjust your water ph in the same temp as the grow room. Because if you checked and adjusted the ph in a 60% room and brought it in to the 75% room , it would probably be off by time it goes through the soil and heats up. I would think that all liquids (ph up, down, nutes , ect) would each vary on how much the temp would fluctuate their ph.... Thus making them different than plain water. So for better control under the process of elimination, I would seem smart to do all adjustments to water at the grow rooms temp, reguardless of the temp compensation of the ph pen. Dont cha think?

What I'm saying is that your ph readings were off, based on the fact your pens and testors doesn't compensate and adjust for different temperature - If you have something ph balanced at 18 degrees, and it was balanced with variences for temp - it would still be balanced at 20 degrees.. or 25. If you adjust your ph with a pen that self adjusts to read appropriately at whatever temp the res is - it will be balanced. I would assume that if you aren't using something like that you would likely have your water sit out to be room temperature..and then adjust it from there as you suggest so you get consistant readings - that makes total sence to me too.

But my pens are the oakton testr ph2 and milwaukee mw801, they do adjust to the temp. And the third tester is the fish aquarium dropper type. Try this test an see if your ph pen does it. Take some tap water from the sink, hot. Test it, note the value, then let it cool ten minutes and again take note of the value. Are they the same?

All I know is when I mix my nutes at 15 degrees, and let it sit out for a few hours before I dump it may go up to ambiant temp (let's say 18 degrees) and it's still balanced. I'll give your test a shot when I get some motivation

Hello. I get balanced PH of water with peat granulat for aqurium filters([h=3]Sera Super-Activ Peat Granulate), , and it brings down my ph from 7.5 to 6.5 in one day and stays stable for a week.[/h]