Organic Hydroponic is an oxymoron if you ask me...you know like..military intelligence or jumbo shrimp....they just don't go well together. ESPECIALLY in dwc. Besides, a lot of people will tell you that the plant uses elements in a "chemical" form no matter how it gets there anyway.
Not saying that "organic" fertilizing doesn't have it's place..it's place just isn't really in my rdwc system. I prefer the mindset of being in a laboratory and being a bit more clinical when running hydro.
Also, in dwc, if you have any root problems, discontinue the use of enzymes until you get the problems cleared-up. Enzymes are for breaking down organic matter into more usable "nutrients" (read chemicals). They tend to lend an explosive growth quality to root pathogens. Again, I prefer a "sterile" res. I don't use enzymes.
You can't use (as was said) H2O2 along with
Great White or enzymes. H2O2 kills shit...that's what it's for.
What I do (ymmv) ...or do NOT do is..use H2O2 except for cleaning. There are other (gentler?) products that will protect you from everything that H2O2 will (and better I think) like SM90 and or DM Zone.
For brown algae (not SM90, DMZone, OR H2O2 will kill that stuff), I have a jar of
Great White on stand-by along with some EWC to make some tea if I ever need it.
I had a scare a few weeks ago so I brewed-up a few gallons of
Great White/EWC tea but it turned-out to be a false alarm.
As I said though...I just have the
Great White in case of a brown algae emergency. Until then, nothing living in my res.
pH swings are/can be good but we're talking a swing from like 5.8 to 6.2 or 6.3 in a week or ten days...not overnight. I have no organic experience though so who knows what that organic "brew" of yours is doing. Maybe that much of a swing isn't that much out of the ordinary for organics but...doesn't sound good to me.
Sounds like root problems imo.
If your temps are going to be that high you should get some DM Zone. You have plenty of air in those buckets?
If you want to take a walk on the "sterile" side (well..you SHOULD spend 30 bucks and make it into a Rdwc either way but...) simply:
-Don't introduce any organic matter into your res if you can help it (except in the case of benes to cure a problem).
-Don't let any light get in
-Try to keep your nutrient temps no higher than 70 (preferably even a bit lower)
-Use SM90 and/or Dutch Master Zone and use the amount DM suggests for your res temps...more for higher temps
-Make sure you have at least 1 Watt worth of airpump per gallon of nutrient solution
-Start with weaker nutrient "strengths". You'll probably find that your plants are happier with much milder solutions than manufacturers recommend (except for the Zone)
........I also have Physan20, Bleach, and H2O2..all used for clean-up and on ..........................stand-by for emergencies.........................
I mix a fresh batch and as the system (plants) use it up, I replenish with pH corrected and SM90 or Zone added RO water daily. My plants use about one to one and a half gallons per day per plant. My 4-plant systems hold around 40 gallons. They've eaten up most of the system's nutes in 7 days so that's when I drain and re-fill fresh.
Now again...I'm not saying Hydro is better or worse than organics....or chemical vs organic or whatever...and I'm not saying that sterile or "dead" reses are better or worse than reses with beneficial bacteria and fungi. A LOT of people have great success with organics, soiless, dwc....and hydro the sterile OR bene route. It's a matter of preference. MY preference is hydro with chemicals and a dead res. YMMV IMHO FWIW!