Ph Dropping From 5.8 To 3.9 Overnight! What Is Causing This?

[RFT]

Just heading to a meeting if it's not a sterile system a lot can be caused by microbes but I'll get into that after.

Sterile within reason. Only synthetic nutes. Calcium Hypochlorite added frequently to mitigate algae and other organics.

 

[Aqua Man]

Sterile within reason. Only synthetic nutes. Calcium Hypochlorite added frequently to mitigate algae and other organics.

Are you cleaning out the dead and decaying organics because that can cause cause PH to drop

 

[RFT]

Are you cleaning out the dead and decaying organics because that can cause cause PH to drop

What dead & decaying organics?

I do a full reservoir clean in between cycles. But since switching to the Calcium Hypochlorite there isnt any visible organic matter to clean up.

Granted, being that it’s in a greenhouse (with sealed floor) Im only going to be able to do so much. It’s NFT. So not easy to keep sealed off like say RDWC.

 

[Aqua Man]

What dead & decaying organics?

I do a full reservoir clean in between cycles. But since switching to the Calcium Hypochlorite there isnt any visible organic matter to clean up.

Granted, being that it’s in a greenhouse (with sealed floor) Im only going to be able to do so much. It’s NFT. So not easy to keep sealed off like say RDWC.

dead algae etc.

 

[Aqua Man]

What dead & decaying organics?

I do a full reservoir clean in between cycles. But since switching to the Calcium Hypochlorite there isnt any visible organic matter to clean up.

Granted, being that it’s in a greenhouse (with sealed floor) Im only going to be able to do so much. It’s NFT. So not easy to keep sealed off like say RDWC.

hmm does your PH change from first thing before lights onand later in the day about an hour before lights out? Can you check this?

 

[RFT]

dead algae etc.

I see. Since switching to Calcium Hypochlorite the algae is almost non existent. And there is zero buildup or sludge on the roots. They are remarkably clean.

 

[Aqua Man]

I see. Since switching to Calcium Hypochlorite the algae is almost non existent. And there is zero buildup or sludge on the roots. They are remarkably clean.

PH stable day and night? You don't see a drop in PH in the morning before lights on then slight rise throughout the day?

 

[RFT]

hmm does your PH change from first thing before lights onand later in the day about an hour before lights out? Can you check this?

I can check/track this. I’d have to get more specific in my notes.

Here’s what I know: pH is set to 5.6 with a 0.8 float before the auto doser recalibrates the solution.

Normally it takes about 3-4 days for the pH to steadily climb to 6.4 and then the computer drops it back down to 5.6

It’s a very generic pH range. By design.

Works fine until week 4. About 4 days in the pH is climbing. I check it at night. I come in the next morning and BOOM it’s down to 4.8 ... same scenario as the OP in this thread.

 

[Aqua Man]

I can check/track this. I’d have to get more specific in my notes.

Here’s what I know: pH is set to 5.6 with a 0.8 float before the auto doser recalibrates the solution.

Normally it takes about 3-4 days for the pH to steadily climb to 6.4 and then the computer drops it back down to 5.6

It’s a very generic pH range. By design.

Works fine until week 4. About 4 days in the pH is climbing. I check it at night. I come in the next morning and BOOM it’s down to 4.8 ... same scenario as the OP in this thread.

Have a way to track you doser? I might try unplugging it and dosing by hand... Equipment sometimes can fuck ya.

 

[RFT]

Have a way to track you doser? I might try unplugging it and dosing by hand... Equipment sometimes can fuck ya.

4 different zones. 4 identical dosers. Super high quality.

6 yrs experience with these dosers. I trust them more than humans or myself LOL.

 

[Aqua Man]

4 different zones. 4 identical dosers. Super high quality.

6 yrs experience with these dosers. I trust them more than humans or myself LOL.

Ok see if the PH is changing from literally just before lights on.... not after and then just before lights out to see where your fluctuations are happening. I kinda feel like there might be a couple things going on here.

 

[RFT]

Ok see if the PH is changing from literally just before lights on.... not after and then just before lights out to see where your fluctuations are happening. I kinda feel like there might be a couple things going on here.

It’s gradual. Happens throughout the night and into the next day. Just keeps sinking until it’s in the 4’s then stabilizes. Or I assume it does. I dont sit around to see what happens. I start adding fresh h2o to raise the pH back up.

What’s your theory?

 

[Aqua Man]

It’s gradual. Happens throughout the night and into the next day. Just keeps sinking until it’s in the 4’s then stabilizes. Or I assume it does. I dont sit around to see what happens. I start adding fresh h2o to raise the pH back up.

What’s your theory?

Well plants do different processes during lights out and day light. They release starches etc and hydrogen ions during lights out so while this may not be huge it can add up with other effects. Like high CO2 levels produced during plant respiration over night. Now air pumps increase gas exchange and so there can be an increase of carbonic acid added together could make a small ph drop that should be reversed during the next day cycle.

What I'm thinking and I need to look into this but I have been very busy lately is with you now increases root mass and other factors. The clorine in the pool shock is destroyed when it comes into contact with organic matter. (You should really look into the nasty by products created from this). As this occurs you are losing your buffering capacity.

I would bet that if you switch to h2o2 and added a buffer like calcium carbonate or potassium bicarbonate (which in flower depending on your base nutes may be beneficial) you would no longer see this ph drop.

Like I say I have read up on this to ensure I have it right bit that what's I am thinking for what it's worth

 

[Aqua Man]

The higher the ppm feed the more it will be affected alao

 

[RFT]

Well plants do different processes during lights out and day light. They release starches etc and hydrogen ions during lights out so while this may not be huge it can add up with other effects. Like high CO2 levels produced during plant respiration over night. Now air pumps increase gas exchange and so there can be an increase of carbonic acid added together could make a small ph drop that should be reversed during the next day cycle.

What I'm thinking and I need to look into this but I have been very busy lately is with you now increases root mass and other factors. The clorine in the pool shock is destroyed when it comes into contact with organic matter. (You should really look into the nasty by products created from this). As this occurs you are losing your buffering capacity.

I would bet that if you switch to h2o2 and added a buffer like calcium carbonate or potassium bicarbonate (which in flower depending on your base nutes may be beneficial) you would no longer see this ph drop.

Like I say I have read up on this to ensure I have it right bit that what's I am thinking for what it's worth

I had this pH drop long before using the pool shock.

I tried H2o2 and lost 1100 plants in under 5 minutes by adding 500ml to my reservoir. Super low dosage. Never again. That was a costly mistake.

So far the pool shock is working great at algae mitigation. And no new symptoms of issues are occurring that werent present all along.

Im going to test increasing the P-K ratio. Everything is pointing to that at the moment. Especially the small/non existent colas. The plants have been getting starved.

Didnt matter which nutrient brand. Raising the EC only exacerbated the imbalance, causing lockout. Lowering the EC didnt result in outright deficiencies but definitely yield loss.

I know Im close to dialing this in. Each run is getting better & better. Many variables have been adjusted many issues eradicated. Just these last few remain.

If adjusting the P-K doesnt work, Im gonna look further into your theory. Heck, Im gonna look into it anyways. But I can only change one thing at a time in this process.

 

[Aqua Man]

Then just use potassium bicarbonate to being the ph up... Imho you don't want high phosphorus. What I was talking about is the pool shock has a high ph so it was buffering the ph but as it's used up you ph is unstable and it's drops like a rock. The bicarbonate is a ph buffer and the extra K you will benefit from if looking for a boost anyways. Ideally K 2x the amount of N. It's will be more stable than just relying on the pool shock

 

[Aqua Man]

As I was saying before the high the ppm the more pronounced it will be because nutrients are acidic and you need to have buffers in the water to stabilize the ph.

Honestly I shit the bed about h2o2 suggestion because I should not have even considered the pool shock as an adequate buffer.

Add 1/4 tsp per 5 gal and see where that takes you stability wise... Better to start low.

 

[RFT]

Then just use potassium bicarbonate to being the ph up... Imho you don't want high phosphorus. What I was talking about is the pool shock has a high ph so it was buffering the ph but as it's used up you ph is unstable and it's drops like a rock. The bicarbonate is a ph buffer and the extra K you will benefit from if looking for a boost anyways. Ideally K 2x the amount of N. It's will be more stable than just relying on the pool shock

Very interesting.

I haven’t noticed the pool shock causing the pH to rise at all.

But I still find your suggestion good. Potassium bicarbonate. I’ll get my hands on some.

 

[Aqua Man]

Very interesting.

I haven’t noticed the pool shock causing the pH to rise at all.

But I still find your suggestion good. Potassium bicarbonate. I’ll get my hands on some.

Super cheap off Amazon or anywhere for that matter.

 

[Aqua Man]

95+% of ph problems are inadequate alkalinity. Aka carbonate, bicarbonate. That's what provides the stability. So many times people will say my ph is rising from say 5.6 to 7 in 12hrs. I will tell them to add a buffer like baking soda (sodium bicarbonate) cause most ppl have it (ideally avoid sodium). Any they are like my ph is rising why would I want to add something that going to increase it. The reason is because then it takes more acid to lower the ph so in the end you get a much more stable ph. Same goes for ph dropping quickly. You have more acid but little buffer and as the buffer is used up the ph drops fast.