ph and nutrient acidity???

sepsis

Member
A quick question here....

I am growing in soil and my water's ph is 7.0.

I have used both Fox Farms Grow Big for veg and GH FloraNova Bloom for flowering (both the bottle and the guy at the hydro store said would work fine for soil.)

The problem is that when I mix up either one with water to feed to my plants, the ph drops to something like 5.0. After that point it takes a RIDICULOUS amount of ph up to bring the ph back up to about 6.8.

Seriously, what gives?? I figured I'd have to adjust for low ph a little but it seems like the ph for both the Grow Big and the FloraNova Bloom want to stay around 5.0. Both nutes say that they are buffered, is this what is causing this issue? And if so, how do I resolve it? And what exactly does buffered mean in the case of nutrients anyway??

I was wondering if maybe it had something to do with the order I do things in: add a bit of water, add nutes, fill the rest of the gallon with water, shake, then adjust for ph. Maybe I should adjust the water's ph before I add in the nutrients?

Has anyone else had similar issues with either of these nutrients? It seems like a lot of people here like to use Grow Big for vegetative growth, so I figured someone would have noticed the ph drop.

Sorry, I know it's a lot of questions, but this has been driving me crazy. :confused:
I am worried that my ph is going to drop unacceptably since the plants are in a potting mix that's mostly peat.
 

bongrippinbob

Well-Known Member
Just about all nutrients will drop your pH. Don't pH the water before you add nutes as it will just drop anyway. There is no way to resolve your issue with the pH dropping when you mix the nutes. That is the reason they make pH up/down.

The higher the PPM of the solution, the more pH up/down is needed. If you are pH'ing plain water, you will only need like 1ml per gallon. But if you are trying to adjust nute solution with a PPM of like 1000, you will need much more.

In my grows, I mix 30gallons at a time to water my plants and I have to add like 100-300ml of pH up depending on what stage my plants are in. So this works out to like 3-10ml per gallon of nute solution. My solution starts at anywhere from 4.5-6.0 depending on what I am using at the time. If I bubble the solution overnight, usually the pH will rise to a usuable level. Or at least get much closer than the 5.0 it started out at.
 

epixbud

Well-Known Member
A quick question here....

I am growing in soil and my water's ph is 7.0.

I have used both Fox Farms Grow Big for veg and GH FloraNova Bloom for flowering (both the bottle and the guy at the hydro store said would work fine for soil.)

The problem is that when I mix up either one with water to feed to my plants, the ph drops to something like 5.0. After that point it takes a RIDICULOUS amount of ph up to bring the ph back up to about 6.8.

Seriously, what gives?? I figured I'd have to adjust for low ph a little but it seems like the ph for both the Grow Big and the FloraNova Bloom want to stay around 5.0. Both nutes say that they are buffered, is this what is causing this issue? And if so, how do I resolve it? And what exactly does buffered mean in the case of nutrients anyway??

I was wondering if maybe it had something to do with the order I do things in: add a bit of water, add nutes, fill the rest of the gallon with water, shake, then adjust for ph. Maybe I should adjust the water's ph before I add in the nutrients?

Has anyone else had similar issues with either of these nutrients? It seems like a lot of people here like to use Grow Big for vegetative growth, so I figured someone would have noticed the ph drop.

Sorry, I know it's a lot of questions, but this has been driving me crazy. :confused:
I am worried that my ph is going to drop unacceptably since the plants are in a potting mix that's mostly peat.



Go do some reading before you bother going nutz up'n your PH, 5-6 is ware you want soil grow PH......... http://www.a1b2c3.com/drugs/mjgrow9f.htm



see my grow... https://www.rollitup.org/grow-journals/107075-ak-47-x-super-silver-42.html

see my DIY.... https://www.rollitup.org/do-yourself/212657-all-one-diy-aero-cloner.html



............................. :joint:
 

bongrippinbob

Well-Known Member
Closer to 5.8-6.8 is much better for soil than 5-6 pH. If you look at any pH chart it shows that at 5.5 pH phosphorous is barely available. Mg uptake as well as calcium uptake will be inhibited as well.
 

sepsis

Member
Just about all nutrients will drop your pH. Don't pH the water before you add nutes as it will just drop anyway. There is no way to resolve your issue with the pH dropping when you mix the nutes. That is the reason they make pH up/down.

The higher the PPM of the solution, the more pH up/down is needed. If you are pH'ing plain water, you will only need like 1ml per gallon. But if you are trying to adjust nute solution with a PPM of like 1000, you will need much more.

In my grows, I mix 30gallons at a time to water my plants and I have to add like 100-300ml of pH up depending on what stage my plants are in. So this works out to like 3-10ml per gallon of nute solution. My solution starts at anywhere from 4.5-6.0 depending on what I am using at the time. If I bubble the solution overnight, usually the pH will rise to a usuable level. Or at least get much closer than the 5.0 it started out at.
very useful info!! thank you. +rep

I figured the ph of the nutes would drop, I am just surprised by how much ph up I have to add (particularly to the floranova.)
I thought 10ml/gal was quite a bit, but apparently you seem to have had to add that much too. That makes me feel a bit better, I thought something really weird was going on with my nutes or my water or something...
 

sepsis

Member
Closer to 5.8-6.8 is much better for soil than 5-6 pH. If you look at any pH chart it shows that at 5.5 pH phosphorous is barely available. Mg uptake as well as calcium uptake will be inhibited as well.
Yeah I've been to keep the ph of the soil between 6.3 and 6.8, and I've been worried about the nutrient uptake problems you've mentioned because a couple of my plants have started looking a bit frazzled, and I was thinking that there was just no way they're deficient, it's gotta be that the soil is getting a bit too acidic for them.
 
some stuff i found, which hopefully helps someone:

"The main ingredient in eggshells is calcium carbonate (the same brittle white stuff that chalk, limestone, cave stalactites, sea shells, coral, and pearls are made of). The shell itself is about 95% CaCO3 (which is also the main ingredient in sea shells). The remaining 5% includes calcium phosphate and magnesium carbonate and soluble and insoluble proteins."

if you dont have the time to make calcium powder yourself go buy and
mix in a bit of gypsum, calcium carbonate or dolomite lime (which are all Ph uppers) into your freshly made medium and you will more than likely avoid this acid problem down the road.

Poor mans method: bake a bowl full of clean eggshells at 200f for about 12 hrs; mimic how you cook beef jerky and you should come out with soluable calcium powder which you can add to you nutes or top the soil with it.

Scientific methods:

Calcium carbonate & aquaponics
http://www.dec.ctu.edu.vn/cdrom/cd6/projects/krib_aquaria/caco3.html
calcium carbonate extraction
http://www.seps.org/oracle/oracle.archive/Expert/forbesm/Physical_Science.Chemistry/2002.05/001020648521.2701

so eggshell aint that bad for a ph upper just decompose em by baking good luck all you mad botanists/scientists out there!
 
At $25/per gal of liquid form Ph UP. Might I suggest something different: calcium carbonate aka eggshells, aka tums. Off brand Tums are very affordable and each have 600mg of calcium carbonate as well as complex carbohydrates like dextrose and sucrose; and 2mg of magnesium.
 

bongrippinbob

Well-Known Member
You have to figure there is almost 3800ml per gallon. So if you are using 10ml per gallon, you are able to make 380gallons. So you are paying like 7cents a gallon to mix your nutes. If you are only using 5ml per gallon you are paying under 4cents a gallon. How much cheaper do you really need to get?
 
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