Hey guys, this is my first post. Ive been doing tons of research but there isn’t a lot out there on Octopots. So I’ll start with a quick background. This is my second grow ever. I just successfully finished a photoperiod run with 3 plants in a 2x4 tent. That was a Promix and dry amendment run which was super easy. This is my second grow and I decided to try 2 autoflowers and Octopots for the first time so this is how I started:
Mixed up Promix HP, dolomite lime and perlite. I added just a handful of worm castings and I actually added some Dr earth to the promix. Very little though. Like 4 Tbs to 12 gallons of media. I then watered each bag with about 1/2 gallon and then planted the seeds that soaked for 24 hours. I didn’t add anything to the reservoir at this point. Both plants sprouted within 4-6 days. After they sprouted I put 1 Gallon of ph water in each reservoir. About 7 days later (day 11-13 for plants) that the water level was low so this is where I added some Nutes. I filled 3 gallons of water and mixed up some silica first, waited then added Calmag and then my Jacks 20-20-20. I then PH’ed the mix down to 5.8 and split the water between the 2 Octopots. I decided to check the PH in the reservoir 36 hours later and saw it was 7.2. But every time I add some PH down and get the reservoir back to 6.2 it will go back up to 7 within 12-24 hours. Ive been trying to do research on what my problem could be so I figured id ask here since this is where I see the most Octopot posts. The Calmag I used was TPS organic so I am not sure if that is the problem. Another important info is I am using my tap water which comes out at 210 ppm and 8.6PH. During my first run, I used to fill a 5 gallon bucket with tap water and PH it to 6.5 and leave it for days and the PH never drifted.
I’ve got a similar problem in DWC. PH to 5.8, 800ppm and it doesn’t budge in the main 15 gal storage res. 8.2ph and 100pmm tap. I’ve ran an RO filter and now <10ppm and 7.5ph. It seems my water is naturally heavily buffered toward a greater than neutral ph and as the plant feeds of the nutes, the acidifying buffer is being pulled or losing its effectiveness and the water drifts.
It was mentioned to be on the lookout for microbial growth in your res, too as it will cause drift. You running anything to sterilize your nutes?
FWIW I also ran 6 gallon Octopots. I used tap water I let gas off for a couple of days, and AN Ph perfect trio (micro, bloom, grow) and never had an issue?
This is in no way a criticism rather a question of maybe too much/many ingredients in the stew?
The trickier I get with Ocotpot the more issues I run into. Coco/perlite/moss mix and simple tpsONE for nutes (single bottle!) has given me the best results. Shoutout to @Gravitys-Rainbow for the advice a couple summers ago. He liked promix I believe but I ended up on Royal Gold Tupur.
I never ph test or anything with octopots. Just let the rez run dry/close to empty before refilling.
With promix i only ever added some extra perlite. I fed every watering with urban farms Vegtable and garden of eden(flower). Calmag was added if i was using ro water.
Also when you said you filled the rez did you completely fill or just to the first line? You dont want to completely fill the rez with seedlings/young plants.
Many octopot growers experience the same thing. It just happens. Unless your plants are looking sick I wouldn’t worry too much.
My nute mix is set to 5.9, but within a couple days in the reservoir it’s up to 6.8
I spent a lot of time trying to keep it stable and low, but just gave up.
The plants are still healthy so I don’t worry too much.
It means your tap water is probably high pH (mine is 9.0) but the nutrients/salts tend to drop it lower (6.2-6.4 ish) and then a little pH down gets it to 5.9
But as the roots absorb those nutrients (that were lowering ph) the ph goes up.
Sometimes if the plants look unhealthy I will empty the reservoir completely and fill with new solution. But that is not often.
I run about 850ppm, and my plants all look like this.
Thanks guys for the replies. So it the PH in the Rez kept creeping up and I kept lowering it but as a result, I was getting over my target PPMs because of the PH down being added. So I decided to empty both 6 gallon reservoirs. I again mixed 3 gallons of tap water with the same exact silica and Nutes but this time left out the CalMag. 1st thing I noticed was that I had to add more Jacks Nutes to make up for the PPM that I was getting from the Calmag. The 2nd thing I noticed was that after mixing everything, my PH stood at 6.1. Before when I added Calmag, I had to PH down the mix at then end almost a whole point. Not sure if the PH was lower because of no calmag added or extra Jacks that was added, or both. I let the mix sit for 45 min and the PH never moved from 6.1 so I divided the 3 gallons up giving each octopot 1.5 gallons.
So now it has been 18 hours and I just checked the Rez and the PH was 6.4-6.5. This is much better so far but I will keep an eye on it. So if my PH does get better, can I assume it was me skipping the calmag this time? or is my PH staying lower from the added Jacks? Also does everyone that runs tap water, run calmag because im not sure I even need it. If the PH does stay within range, I will try a different Calmag next time. One without organics in it like Calimagic. Last point, is both plants look happy but there are no roots in the Rez so I am not sure how much those PH swings were really effecting their growth.
I have and the PPMs have only gone down a tiny bit. After doing some more thinking. I really wish I didn’t add that little bit of worm castings, and dry amendments, and lime to the media. Could that be messing with my PH since that media is sitting in the water partially?
Were the plants showing negative signs? I really wouldnt worry about the PH drift imo, that is one of the best things about octopots is there ability to be almost fool proof.
no they both look fine. I will try and ignore it for now. It’s hard to ignore though because I feel like I am doing nothing as it is already with this grow. haha
Sorry, I’ve just reread the thread and seen that the roots aren’t into the water yet, so my guess was misguided.
If they’re looking ok there’s a lot to be said for leaving them well alone. Back in the 2000s my pH pen broke and I continued growing and didn’t ever pH adjust and nothing bad happened. Currently my ppm meter has died so I’m winging it and just following the ml/L feed chart and they’re actually looking better than when I try to micro manage the nutrient levels.
Yea im just gonna let it go and see what happens since the plants look happy. I just checked both reservoirs. it’s been about 40 hours now starting at 6.1-6.2. One of the reservoirs is 6.8 and the other 7.0. I just saw a small root reach the water on the 7.0 res so we will see if that changes anything. Took 16 days from sprout to hit the water. The other is 2-3 days behind.
Honestly i dont think PH is thay big of a deal in non DWC environments. Unless your water is extremely alkaline or acidic. Promix is ph buffered. If you are in 5-8 range i think you will be just fine.
Just wanted to update the thread for anyone out there researching on the web. So After taking out the calmag, PH was still drifting to 7.-7.2 but took 72 hours to get there versus the 30 hours it took before. One important thing I forgot to mention is I was adding Pure Blend Tea after the silica. I didn’t think anything of it because it’s just basically beneficial microbes with a NPK ratio or 0-0-.5.
So now it was time for another refill of the 2 reservoirs. I mixed 4 gallons together in a bucket and split it between the 2. This time I kept it as simple as I could. I added silica first, mixed it in and waited about 20 min. Then I just added the jacks nutrients. So this time just silica and Jacks. I ended up with a solution of 5.4 so for the first time, I had to add PH Up instead of down this time. I PHed to 6.0 and sent it. 24 hours later, it was at 6.0-6.1 and now over 48 hours later it’s still at 6.1-6.2. So for me, I think it was the Pure Blend Tea I added that was throwing the PH off.
I know this isn’t probably helpful to a lot of experienced octopot growers but I may still update this thread for research purposes in case anyone else is having the same problems as me. I am not sure if I even need calmag. Plants look really healthy but are only on day 20. I will probably introduce calmag back in to see if it was just the pure blend tea. This time, I will use a non organic calmag like calimagic and not the TPS one I did before. Thanks for your replies! I can finally sit back without constantly worried about the PH…for now. lol
Hey Brian, I found out the hard way, organics and reservoirs don’t mix well. I am using Fox Farm nutes and had root problems because of the organic nutes. I was also topping off the reservoir instead of letting it go dry.
Heavily filtered organic nutes are not bad. I switched to the hydro setup of Fox Farm nutes and it still calls for Big Bloom. Have not had problems since. I add 1/3 teaspoon slf-100 as well.
It could be a mix of factors. High PPM, alkaline tap water (210 ppm, pH 8.6) can resist pH adjustments, and the organic TPS CalMag might be releasing compounds that gradually push the pH up. Also, the Octopot material itself may leach substances over time. I’d recommend pre-mixing your nutrient solution in a separate container, letting it settle for a few hours, and then topping off your reservoir
thank you. In my experience, I am starting to think the same thing with organics in the reservoir. Because now I added calmag back in a 1/4 strength. But this time I bought calimagic instead of the organic TPS. My PH goes up maybe .7 over 7 days which is acceptable to me. With the other calmag it would go from 6.0-7.2 in a little over 48 hours. Im gonna try calimagic at 1/2 dose next fill up.
Simple and easy.