You might increase your dosage rate. What you're applying isn't killing the core pathogen load. Try a one-time dose of 50% grade @ 5ml/L (8.5ml for 35%), then return to 1ml/L (or 1.7ml/L for 35%) every 3-4 days, see if it doesn't cooperate. If you're using a flood system, pour about a litre or so of the high dose soln through the tops of the plants to assure that all of the rootmass is being treated.
The only thing I haven't done is to pour concentrated soln through the pellets & existing roots. I though that may kill-em-all, so to speak!
I haven't seen the Hanna pumps. Got a link?
After all, we're stoners here and remembering to do certian tasks can be somewhat beyond us.
I had links but forgot to put them in...damn!
HANNA Instruments Dosing Pump, w/ Timer
and
HANNA BL 7916 pH Controller + Dosing Pump, BL7916
The dosing pump is doable...the pH controller is actually not too bad, but out of reach at the moment - if you know what I mean!
There's a couple of causes of rising pH. Rockwool will do it as a result of some residual limestone dust in the material. This is one of the reasons that one should soak RW cubes used for cloning in a 5.0 soln for 24h and fully drain the cubes with a salad spinner before plugging stems in them.
Next time I'll soak em, not just "dip" em!
It is not practical to presoak RW floc as it's hard to sufficiently drain the material of the presoaking soln. When I was using pots stuffed with only RW floc, a .1 rise after the 1x/day flood was the norm. I shot the pH a bit low, 5.6 usually (in the fond hope that the actual rootzone pH would be 5.8 ) and corrected tank pH down when it got over 6.0. pH is a lot more stable with my present media, Fytocell.
I don't use floc. I root seedlings in 1.5" cubes, then place them in 5" net baskets, in Hydroton pellets. The 5" baskets are put in 2gal flood buckets w/pellets. I too have been shooting low (5.5-5.7), and now that the cubes are up out of the flood zone, the plants are improving every day. The pH still keeps climbing, though....
Another very common cause of rising pH is pathogens in the system, notably pythium and fusarium.
I figured that's what the primary source of the rise is...but can't seem to kill that crap off no matter how much I clean, or concentrate the H2O2 soln.
On 9-15 I (again) drained and cleaned out my hydro system. Added approx 135L H2O, than I added 1000ml H2O2. I left the plants out of the system overnight, and I let the system flood every 2 hours until 0600. Then I added another 250ml H2O2, waited 20 min, added nutes, and let the system sit for another 2hours. At about 1100 I corrected pH to 5.8 and at 1200 I began flooding the system @2hour intervals until 2200 hours, lights out at 0 hour.
After I added the H2O2 to the water that came out of my tap, the soln sounded like I had poured a glass of soda. Is that normal? The soln actually gets milky before it gets clear. The milky look appears to be oxygen being released into the water...maybe consuming pathogens in the spring water? Could we have a huge pathogen load in the water here that I am having a problem overcoming? That's why I let it sit in a concentrated soln overnight before doing anything else, hoping to kill off the pathogens.
Thanks Al!
Is it normal for the pH to want to climb a little bit all the time? or should it stabilize and say at like 5.8 for a couple of days? My pH is always wandering up. It can be 5.8 just before a flood, but an hour after the flood it is 5.9. The pH goes up fairly consistently .1 or .2 per flood. Is that normal? Am I being repetitive?
kinda faith...no offense meant.
