5 wk of bloom, pH rising 1-2 points per day ????

This is my first hydro, I've had a few soil grows before that returned good results. I stumbled across Emilys Garden on Amazon, and decided to give hydro a try. See attached pics ( The one pic is from approx 3 months ago (ended up with 4 males that got culled).) I ended up with 2 females that I've had in bloom now for 5-6 weeks. Up until now, it has been working pretty well. But approx 14 days ago I started having trouble with the pH rising every day. I try to keep it at 5.5-5.8, but over the course of 4-6 hours it will rise to 6.6 Seven days ago I took apart the system and cleaned it with H2o2, and ran it with a water / h2o2 solution for a day. Then I went back to my nutrient solution (Flora Nova Bloom 5ml/gallon = 1200 ppm), but my rising pH problem came back. I try to keep the pH at 5.5-5.8, but over the course of 4-6 hours it will rise to 6.6 I'm using RO water for everything. On an average day I might be adding 5 ml of pH down to my system (the Emily's garden thing has about a 2 gallon reservoir). Concurrently with the pH problem, the plants started showing some nute deficiency signs, and the buds started to stretch a bit (I'm assuming both are from nute lockout caused by pH).

The roots look great. They practically fill up the entire reservoir. I've actually wondered if the root system is too thick for some reason... I'll take a pic of them and attach later. However, this system is only a 2 gallon bubbler, so I'm wondering if the pH problem is just from the fact that I'm growing 2 healthy girls in a system thats just way to small? As a test to that theory I decided to start changing the nute solution every other day, but that didn't help either.

I was running my ppm between 2,000 - 3,000 a few weeks ago, and then started backing it down. I'm wondering if because of the decreased nutes (currently 900-1,300), I'm now suffering from some destabilization of the nute mix due to rapid uptake by the 2 plants in the small hydro system? Should I up the ppm again to 2,000 ? Or try some root inoculant like subCulture M to out-compete whatever organism(s) might be throwing off the pH? Or run some FloraSheild? Or ???

So, any thoughts? I need about 2 or 3 weeks to finish out, so any ideas would be appreciated!

What's your water temp at?

Water temp is about 65

Don't worry about that, Even after i bought my RO-DI filter, water will rise upto 8 if i don't adjust it at least once a day. I try to reset it at 5.8 twice a day. A full water change helps alot if you have RO water, but after few days in the reservoir the ph will start to raise again. I don't bother with it, keep it at 5.8 once or twice a day and the gurlz will be happy.

Are your nutes organic or chemical? If chemicals i would not suggest 2000-3000ppm.

Here's the pics as promised...

View attachment 952498View attachment 952499View attachment 952500View attachment 952501View attachment 952502View attachment 952503

I'm using the FloraNova bloom, so I don't think those are organic... I increased the nutes to about 1400 this morning, and it seemed like the pH was a little more stable for a few hours. It also seems like the ladies really drank deep - the ppm was down to 950 by the afternoon, but the pH was up again (had to add 3 mL of pH down to my 2 gallon system). I'm going to try upping the nutes a bit more tonight.

Just an FYI, I finished up about a week ago, and the roots weren't in great shape. I don't think they were in a full-on classic case of root rot, but they defintely weren't healthy. You could see some new healthy roots coming out the bottom of the pots, so I think the sick/dying old roots were the cause of the pH problem. I never did get the pH under control - I tried H2O2 and Florashield. I just monitored the pH 3-4 times a day for the last 2 weeks to help them finish out.

It was probably your media, those hydroton get oversaturated with the nutrients in the water through your grow and really mess up pH.

-V