pH of water I'd previously adjusted seems to be changing over time.

[radagast97]

In preparing my plant water, I add a small amount of buffering agents, which are also fertilizers, to non-chlorinated water. I then adjust the pH to about 6.5. I do this in 5-gallon batches, which lasts about a week or two. I have only a few plants. Recently I've also been using this as a base for making a compost tea.
I have never checked the pH of the water after making it but did just a few days ago and noticed the pH had risen dramatically. Up to about 8.5. I've been checking since and the pH has had a tendency to creep up.

This was a bit surprising. Has anyone seen this before? Does anyone have a clue as to the cause?

Thanks

 

[Zen_Seeker]

In preparing my plant water, I add a small amount of buffering agents, which are also fertilizers, to non-chlorinated water. I then adjust the pH to about 6.5. I do this in 5-gallon batches, which lasts about a week or two. I have only a few plants. Recently I've also been using this as a base for making a compost tea.
I have never checked the pH of the water after making it but did just a few days ago and noticed the pH had risen dramatically. Up to about 8.5. I've been checking since and the pH has had a tendency to creep up.

This was a bit surprising. Has anyone seen this before? Does anyone have a clue as to the cause?

Thanks

Hi, just before I stopped PHing my water I noticed if I made wormcast tea and checked everything was at 6.3’ish if I put some away for later or foliar spray it would climb the next day. A full point or more.

I’m guessing things are still cooking in the tea or fertilizer and they reacted. I used PH down but never looked further than that.

 

[radagast97]

Hi, just before I stopped PHing my water I noticed if I made wormcast tea and checked everything was at 6.3’ish if I put some away for later or foliar spray it would climb the next day. A full point or more.

I’m guessing things are still cooking in the tea or fertilizer and they reacted. I used PH down but never looked further than that.

My compost tea had used some wormcast compost as well.

I will use pH down if I think the nutrient conc is too high but this time I used diluted nitric acid. I figure a little more nitrates might be appreciated by the babies.

 

[Observationist]

Hi, just before I stopped PHing my water I noticed if I made wormcast tea and checked everything was at 6.3’ish if I put some away for later or foliar spray it would climb the next day. A full point or more.

I’m guessing things are still cooking in the tea or fertilizer and they reacted. I used PH down but never looked further than that.

Carbonate in the water (?)

 

[Captspaulding]

Carbonate in the water (?)

Refrigerate?

 

[Zen_Seeker]

Carbonate in the water (?)

At the time it was wormcastings, molasses, epsom, and something else I think.

Molasses was mixed in with warm water. Tea sat for a full day, no more than two. Then gets mixed into a 7L jug. Most is used as tea that day while the rest is put in spray bottles watered down. Epsom is added when put into jugs. This was made the night before.

I’ve tried a few mixes this was the first with molasses. Can’t say if it helped but I don’t think it hurt. Supposed to help Mycorrhizae I think? Probably bro science.

 

[Observationist]

At the time it was wormcastings, molasses, epsom, and something else I think.

Molasses was mixed in with warm water. Tea sat for a full day, no more than two. Then gets mixed into a 7L jug. Most is used as tea that day while the rest is put in spray bottles watered down. Epsom is added when put into jugs. This was made the night before.

I’ve tried a few mixes this was the first with molasses. Can’t say if it helped but I don’t think it hurt. Supposed to help Mycorrhizae I think? Probably bro science.

Molasses feeds the microbes.

Can cause population booms, the microbes get a bunch of food, eat, divide and multiply, eat, food runs out, alot of them die off.

 

[radagast97]

Carbonate in the water (?)

No.

Some urea. Urea might be converted to ammonia via bacterial action. That's the only thing I can think of.

 

[radagast97]

Molasses feeds the microbes.

Can cause population booms, the microbes get a bunch of food, eat, divide and multiply, eat, food runs out, alot of them die off.

Yeah but typically bacterial action on sugars yields acetic acid, not a base.

 

[Observationist]

No.

Some urea. Urea might be converted to ammonia via bacterial action. That's the only thing I can think of.

Tap water?.

Can release carbonic acid sitting out

 

[Cirroji]

Molasses feeds the microbes.

Can cause population booms, the microbes get a bunch of food, eat, divide and multiply, eat, food runs out, alot of them die off.

mmmm reminds me of how i learned not to share syringes in my different nute bottles haha lord.. i think i created more life than wilt chamberlain doing that.

 

[Zen_Seeker]

Tap water?

If still talking about that tea, yes it was city tap water. Most sat for a day but enough hot water to melt the molasses was used to add to 2+ gal open bucket.

Haven’t made it since but I’m due. (I don’t foliar in flower.) Clones could use a hit about now. I don’t PH any more but I’ll check and pic just to see if it’s duplicated.

 

[mysticepipedon]

Tap water?.

Can release carbonic acid sitting out

CO2 in the air would slowly add carbonic acid to the mix. I think whatever is going on is the result of microbes working on the nutrient mix, or a slow reaction of the nutes, themselves.

 

[MIGrampaUSA]

Actually here's what is going on ... the source water has a high level of alkalinity. (Yes, likely calcium carbonate/bicarbonate) It's acting as a buffer against the pH down and/or nutes and raising the pH over time. This is normal when using water that has a high alkalinity.

 

[radagast97]

Tap water?.

Can release carbonic acid sitting out

Remember, this was highly buffered water. There just couldn't be that much dissolved CO2.

 

[radagast97]

Actually here's what is going on ... the source water has a high level of alkalinity. (Yes, likely calcium carbonate/bicarbonate) It's acting as a buffer against the pH down and/or nutes and raising the pH over time. This is normal when using water that has a high alkalinity.

Perhaps you didn't read the initial post. I buffered the solution to 6.5. THEN the pH rose significantly.
I'm a chemist, I wouldn't trust tap water to be the right pH out of the tap.

 

[MIGrampaUSA]

Perhaps you didn't read the initial post. I buffered the solution to 6.5. THEN the pH rose significantly.
I'm a chemist, I wouldn't trust tap water to be the right pH out of the tap.

No, I actually did read your post. Your water is behaving exactly how I would expect it to react if it were "hard water."

Alkalinity means that over time, there's more alkaline buffers in the water source than the pH down that you used to reach 6.5 pH. This is normal behavior when it comes to water with "high alkalinity." Once the buffering neutralizes the acid, the pH begins to rise again. You might have to adjust your water source several times to actually see it stabilize.

 

[growsince79]

Perhaps you didn't read the initial post. I buffered the solution to 6.5. THEN the pH rose significantly.
I'm a chemist, I wouldn't trust tap water to be the right pH out of the tap.

Whats the ppm? You can't really ph distilled water-and you shouldn't even try.

 

[MIGrampaUSA]

Whats the ppm? You can't really ph distilled water-and you shouldn't even try.

If I were to guess by the way his water is behaving ... it's well water.

But if a person were to try to attempt to "pH" distilled water, I can see real problems getting it to stabilize since there's zero minerals (buffers) in it to begin with.

 

[flowerdave]

When i worked in the greenhouse this was always the case. We would use sulfuric acid to lower the ph and most importantly the alkalinity. The next day the ph would always go from 5.8 to 6.8 but if i tested the solution for alkalinity it was always what it was adjusted to the day before. We always paid more attention to alkalinity vs ph