ph Fluctuation (in ag)

Hey everyone,
It's been quite a while since I've posted here, mainly due to my job. Basically I've got the aerogarden setup in my closet and I've been running into a few problems as of late. I just began germinating seeds in the ag, I put them in about 24 hours ago to be exact. When I first filled up the reservoir, the ph of the distilled water was about 6.0. Today when I went to go check it the ph read around 7.4. I have an airstone running 24/7 in the res and the plants are nowhere near big enough to be offsetting the acidity of the water. I'm wondering if anyone here could shed some light on the problem? It would be greatly appreciated! Thanks!

Rockwool can bounce ur ph.. Are u using it?

Assuming no nutes added yet..

umm... tell us more.

more info definetly...

No nutes as of yet. The setup i'm using uses a sponge medium. I literally added nothing, I'm lost at this point. The setup has a 1 gallon res, so it's pretty susceptable to change.

I'm kind of lost here, does the AG instructions say to grow plants in water only? I keep reading about guys who don't put nutrients in their hydro systems, so I was wondering.

I have always used hydro nutrients in the water that I use on my plants.

Always ... except for periodic flushing.

HTH

Same here, I started my hydro plants w/ nutes. GH three part, I have actually never had to TOUCH the PH. The nutes actually balance it perfectly. Try General Hydroponics three part, follow the guides on the back for seedlings, veg, flower, etc and you should be better.

Thanks for the replies guys, I appreciate it! I was always under the impression that when you germinate and sprout it's not good to have any nutes in the system. According to the aerogarden instructions you're supposed to not feed them until week two, after sprouting. I have a feeling that the aerogarden might still have had some old nutrient salt buildup on the sponge medium? that's the only thing i could think of considering I scrubbed everything pretty clean.


I have an airstone, i have a feeling this might have something to do with it. The temperature fluctuates between 70 and 80 overnight. Since more hydrogen ions mean a lower ph and more hydroxide ions make for a higher ph, is it possible the O2 from the airstone is somehow bonding to the hydrogen atoms to get OH-? I'm so lost.

Im still tryin to figure out this whole sponge medium thing......

a healthy system slowly goes alkaline

make sure your ph tester is clean
i ran my ag with a ph of 6.5 to 6.8