Reasons for Ph Swing

[allgrownup]

BBurnin, I have bought ST at Lowes before as well. Its hard to see. Its a very small bottle. it usually is hanging by a cardboard package. i've never seen a bottle on a shelf.

Look hard. You can also purchase direct from their site as well as request a free sample. The free sample will last you a grow most likely.

 

[Stoney Bud]

Is it normal to have greyish slime on the roots in hydroponics.. for some reason i came home from camping..and my plants look great.. minus the slime on the roots in the water....

No, it's not normal. Has light been hitting your nutrient solution? It may be algae growth. Is you pH jumping around?

 

[RatherBBurnin]

ph is jumping all over the place... but i dont see how light could be getting into my res....... its sealed and no holes..

 

[DLtoker]

It's the lemon juice you are using for pH down man.

 

[RatherBBurnin]

but it was doing the same ish when i was using fish tank ph down.... or is that just as trash as lemon juice?

 

[DLtoker]

Ah, IDK. I believe it would be safe to assume the fish pH adjustment chems are very similar to hydro. I guess this one is over me at this time. Everything that has been brought up in this thread seems reasonable... but the biggie, no algae, then I have no idea. Maybe I'll crack out a good old book and see what I can dig up for other possibles.

 

[RatherBBurnin]

I think what i am going to do when the light turns on in 6 hours is... switch out the solution... im going to rinse off the roots with some water... and see what happens...

The roots are still white..they dont look like they are rotting.. and the sludge comes off very easily when i try to get it off

 

[Stoney Bud]

The lemon juice may be causing some sort of bacteria growth because of the natural sugars in it. Also, fish tank ph adjustment isn't good for plants. It can cause lockout of nutrients which could also be part of your problem with ph.

I would advise you to buy some *plant* ph adjustment and stop using the lemon or fish tank stuff.

Also, if you're in DWC and don't have enough water agitation via the air pump, it could also cause bacteria problems.

Heat would complicate it as well. Your reservoir water should be as close to 75F as possible.

If you're going to go with hydro, start buying the stuff that's made totally for hydro. Trying to take the cheap route always backfires. Buy the good stuff and you'll have much less problems.

 

[RatherBBurnin]

heres the part i dont understand....
If i use tap water.. my tap water is 7.8ph.. i add the nutes and it drops to 7.0...
If i use the bottled water it starts with 7.0ph...and when i add nutes it comes back at 3.5.... does that make sense??? i went to the hydro store today and he closed early on me.. so tomorrow im there to get some ph down and ph up... and some neem for the spider mites...

 

[KADE]

Ack!!! spider mites!? i wish u luck with that battle!

 

[MergeLeft]

heres the part i dont understand....
If i use tap water.. my tap water is 7.8ph.. i add the nutes and it drops to 7.0...
If i use the bottled water it starts with 7.0ph...and when i add nutes it comes back at 3.5.... does that make sense??? ..

I was never good in math but here goes: the ph scale is exponential- like the richter scale. 7.8 is almost 10x higher than 7.0. So your nutes bring the number down in proportion.

Ok, I'm even less good at explaining it. But I think the explanation is the exponential scale.

 

[RatherBBurnin]

I still dont understand how 7.0 gets halfed by adding nuts but 7.8 only goes to 7.0.... that math just doesnt work... and the nutes said it would drop 1 ph level after added the nutes...

 

[MergeLeft]

Go backwards with the math. 7.0 is 10x higher than 6.0, 6.0 is 10x higher than 5, etc. It would take much more acidic content nutes to go from 7 to 6 than it would from 6 down to 3.5.

 

[MergeLeft]

This link even has a place to "practice" the ph math (over my head lol) Here it is with their explanation and chart.

http://www.elmhurst.edu/~chm/vchembook/184ph.html


"The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic.

The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the next higher value. For example, pH 4 is ten times more acidic than pH 5 and 100 times (10 times 10) more acidic than pH 6. The same holds true for pH values above 7, each of which is ten times more alkaline (another way to say basic) than the next lower whole value. For example, pH 10 is ten times more alkaline than pH 9 and 100 times (10 times 10) more alkaline than pH 8.

Pure water is neutral. But when chemicals are mixed with water, the mixture can become either acidic or basic. Examples of acidic substances are vinegar and lemon juice. Lye, milk of magnesia, and ammonia are examples of basic substances."

FYI the logarithmic Richter Scale for earthquakes is the same type of thing & this helps me to understand the ph thing. When it comes to science & math, I take the experts words for it, and try to wrap my head around the general idea. But if you ever been in a 7.0, you know the diff between that and a 6 is MUCH bigger than the difference between a 3 and a 6.


"The Richter Scale is a logarithmic function that uses the common base, 10. The equation is:
M = 10 R or R = log M

Where M is the amount of ground movement (strength of the earthquake) And R is the strength of the earthquake on the Richter Scale. Because the Richter Scale uses a base of 10 each increase of 1 in the strength of an earthquake on the Richter Scale means that there is 10 times as much ground movement.

The amount of energy in an earthquake increases by a factor of 1000 (also called 3 magnitudes) when the value on the Richter Scale increases by 2. The equation for the energy in an earthquake is: E » 31R

Where E is the factor the energy increases by and R is the increase in the value on the Richter scale. For example, there is 1000 times more energy in an earthquake that measures 6.8 than one that measures 4.8 on the Richter Scale.

 

[RatherBBurnin]

But it was going from 7.0 to 3.5... when using bottled water..
and only 7.8 to 7.0 using tap water.. even then the math doesnt work out...

I got the answer i think at the local shop... because i am using RO water there is barely any content to it.. so when i add the nutes.. it makes it very acidic.. however the town tap water has a higher ppm with other additives.. which makes the nutes less potent hence bringing the ph down less...

At least thats what i was explained by the hydro guy...

 

[futuredream45]

Yeah, I have good well water... around 7.4-7.8 (depending on what time of year) When I add the bloom A+B, DNF black/gold, bloom enhancer it drops my ph (in 60 liters) down to 5.8... perfect for blooming.... In your case you'll need to bring it up a bit...
Veg from 5.8-6.2 Bloom from 5.6-5.8 with dnf.

I also have the ph problem, and it really drive me crazy.:hitchair: Kade, you mean if I get these DNF you mention about, the ph will down to the number i want. How long the ph can stay in the number?

 

[RatherBBurnin]

All you need to keep a stable PH is the right ph buffers... ive learn that the really hard way...

 

[futuredream45]

All you need to keep a stable PH is the right ph buffers... ive learn that the really hard way...

Where can i learn the ph buffer ??

 

[MergeLeft]

But it was going from 7.0 to 3.5... when using bottled water..
and only 7.8 to 7.0 using tap water.. even then the math doesnt work out...

You're right RatherBB it doesn't make sense based just on the logarithmic scale. I was thinking the scale went from 1-up, but it has to go both directions from neutral 7.0. This cleared it up for me & to correct my errors in preceding posts on this thread, this is from Spectrum Analytic's Agronomic Library (topic: soil ph):

The soil pH scale is logarithmic; meaning that each whole number is a factor of 10 larger or smaller than the ones next to it. For example if a soil has a pH of 7.0 and this pH is lowered to pH 6.0, the acid content of that soil is increased 10-fold. If the pH is lowered further to pH 5.0, the acid content becomes 100 times greater than at pH 7.0. The logarithmic nature of the pH scale means that small changes in a soil pH can have large effects on nutrient availability and plant growth.
http://www.spectrumanalytic.com/support/library/ff/soil_buffer_ph.htm

 

[MergeLeft]

Where can i learn the ph buffer ??

I think "buffer" is the additive used to help keep ph stable. The property of water to resist changes in pH is known as "buffering capacity,"which is made up of dissolved minerals which tend to keep pH stable.

Buffering capacity is measured by total hardness in your water. By testing total hardness can you predict whether your pH will remain stable after it is adjusted to the appropriate level. (A reading of 4-6 dH or higher is recommended in aquariums to keep ph stable). Adding nutes and the growing process tend to lower ph.

RBB, what the hydro guy explained make sense (unlike me:huh: ) - the salts and minerals which buffer water against ph dropping have been taken out of ionized water. So you have to use an buffer agent. They raise ppm and contain salts I have read elsewhere may not be so great for mj but I defer to RBB who has the experience.

RBB do you use an added buffer agent? BTW why the ionized water- is it to keep ppm low?