Ph up and ph down

anthony1

Well-Known Member
Just trying to see what are you guys Used and the regular General hydroponics Ph up and down seem very weak to me.
 

Herb & Suds

Well-Known Member
Just trying to see what are you guys Used and the regular General hydroponics Ph up and down seem very weak to me.
They are
So people don't get injured
There are stronger products but the danger is in a spill
I rarely use PH down buy only a pint
 

xtsho

Well-Known Member
I buy phosphoric acid by the gallon for pH down. It's not pure and has been diluted but even so it will burn your skin.
 

Erndog

Member
General Hydroponics PH is too weak. I was just pouring from the bottle and seems like I wasn't getting anywhere. I switched to a more concentrated PH.
 

Attachments

xtsho

Well-Known Member
$21.95 a gallon. Takes me a tablespoon / 14.5 ml to bring 4 gallons of nutrient solution down to 6.0 from around 7.2 - 7.5. So it's pretty strong stuff. Phosphoric acid is phosphoric acid. No need to spend three times as much for a fancy name.

 

Erndog

Member
14 ml per 4 gallons is weak. I would have to use about 200 ml for my 55 gallon reservoir. I would need to buy a 1 gal bottle every 20 days. I've had my concentrated bottle for about 2 and half months and only half gone, only use about 40 ml to get to 6.0 from 7.2. In the long run you save money. If your not using alot of gallons of water then you should get weaker stuff so you dont over do it
 

xtsho

Well-Known Member
14 ml per 4 gallons is weak. I would have to use about 200 ml for my 55 gallon reservoir. I would need to buy a 1 gal bottle every 20 days. I've had my concentrated bottle for about 2 and half months and only half gone, only use about 40 ml to get to 6.0 from 7.2. In the long run you save money. If your not using alot of gallons of water then you should get weaker stuff so you dont over do it
You can't say it's weak. Lowering pH is not a static "one measurement fits all". There are many factors that need to be taken into account. Initial starting pH of the water, nutrients used, additives, etc... Many additives lower the pH so if you're using additives that do you would need less ph down. I use tap water, base nutes, and no additives that lower pH. I've ran large reservoirs when I was doing flood and drain and I used the same product then as I do now. That AN costs three times as much but there is no way it's three times as strong if at all.


If the strength is your primary concern then:

One gallon 85% food grade phosphoric acid $39.45& FREE Shipping. You aren't going to get anything stronger than that. Wear gloves and eye protection when working with it.

https://www.amazon.com/Gallon-Grade-Phosphoric-Remover-Clean/dp/B06XZSW3QX/
 

OldMedUser

Well-Known Member
I use concentrated sulfuric acid for down and if I ever need up I just use potassium silicate.

I've use pH Perfect nutes for years with RO water and never bothered with checking pH at all but recently started using Mega Crop nutes. I checked how they come out and in RO water with 1g/L the pH was 6.0. Using our tap water which is around pH 8 and 400ppm the the pH came out at 6.5 at 1g/L so I shouldn't be needing to bother checking pH with these nutes either. I just use RO 99% of the time.
 

xtsho

Well-Known Member
I use concentrated sulfuric acid for down and if I ever need up I just use potassium silicate.

I've use pH Perfect nutes for years with RO water and never bothered with checking pH at all but recently started using Mega Crop nutes. I checked how they come out and in RO water with 1g/L the pH was 6.0. Using our tap water which is around pH 8 and 400ppm the the pH came out at 6.5 at 1g/L so I shouldn't be needing to bother checking pH with these nutes either. I just use RO 99% of the time.

Sulfuric Acid works just fine and is extremely inexpensive as well. You don't have to buy anything fancy to lower or raise pH. I still have a 1 pound container of sodium hydroxide/lye that I got for pH up over ten years ago. Cost $3.99 at ACE hardware. I never have the need to raise pH now that I'm not running large reservoirs for flood and drain.
 

OldMedUser

Well-Known Member
Sulfuric Acid works just fine and is extremely inexpensive as well. You don't have to buy anything fancy to lower or raise pH. I still have a 1 pound container of sodium hydroxide/lye that I got for pH up over ten years ago. Cost $3.99 at ACE hardware. I never have the need to raise pH now that I'm not running large reservoirs for flood and drain.
Silica works well for pH Up and is good for the plants. I have a bottle of pH Up and it's just potassium hydroxide so I evaporated some as I needed the pot. hydroxide for using with EverClear to do the Beam's test for CBD. Then I got a pound of pure pot. hydroxide for that.

I wouldn't want to have to use sodium hydroxide too much as the sodium isn't good for the plants. Cleans out thermos' real good tho. I have a big jug of that and a heaping tsp in a thermos of hot water cleans them out like new. I bought a new 2L Aladdin SS thermos years ago and ruined it by using bleach to clean it. Turns out they use silver solder to seal the base and the bleach eats it out then they lose vacuum and don't work no more. Caustic soda doesn't react with silver and does a better job as well.

:peace:
 

xtsho

Well-Known Member
Silica works well for pH Up and is good for the plants. I have a bottle of pH Up and it's just potassium hydroxide so I evaporated some as I needed the pot. hydroxide for using with EverClear to do the Beam's test for CBD. Then I got a pound of pure pot. hydroxide for that.

I wouldn't want to have to use sodium hydroxide too much as the sodium isn't good for the plants. Cleans out thermos' real good tho. I have a big jug of that and a heaping tsp in a thermos of hot water cleans them out like new. I bought a new 2L Aladdin SS thermos years ago and ruined it by using bleach to clean it. Turns out they use silver solder to seal the base and the bleach eats it out then they lose vacuum and don't work no more. Caustic soda doesn't react with silver and does a better job as well.

:peace:

Potassium silicate can be used to increase the pH. Potassium hydroxide is what the VitaGrow brand I use puts in their pH up. That's the standard for the most part but some commercial hydroponics growers use sodium hydroxide and I've even read articles from major universities that reference sodium hydroxide to raise the pH. The small amount of sodium isn't going to cause any problems. But I never need to raise the pH I only have to lower it after mixing solution with the way I'm growing today. I'm sure glad to be done with flood and drain. It's a great way to grow but changing out reservoirs and monitoring pH levels takes time I don't want to spend. Now I mix, pour, and refill when low.

"The pH is adjusted if necessary by adding acid (dilute sulfuric acid) to lower the pH or an alkali (dilute sodium hydroxide (NaOH) solution) to raise the pH."

http://factsheets.okstate.edu/documents/hla-6442-hydroponics/
 

OldMedUser

Well-Known Member
"The pH is adjusted if necessary by adding acid (dilute sulfuric acid) to lower the pH or an alkali (dilute sodium hydroxide (NaOH) solution) to raise the pH."
I got no beef with using NaOH instead of KOH but just prefer using something with benefit to the plant to something that could be detrimental if used often. I rarely need to use pH Up either so it's not a big deal.

Like I find it distasteful to use pool shock in a sterile hydro grow rather than peroxide because of the extra chlorine added with pool shock where peroxide has no harmful residue at all.

When I bought this house the guy had a water softener hooked up and as they used that water in their garden he used potassium chloride for the brine tank rather than sodium chloride even tho it costs up to 3X as much. I put that damn thing on bypass after about 6 months and now I plan to use the old brine tank for RO storage once I get my own system up and running. I'll hook in a bypass for it too so I can fill 5gal water jugs for us to use and the brine tank for the plant's water storage. 150L and I already have a couple of float valves so can put one of those on it and a fitting on the bottom to feed right into the grow room.

:peace:
 

xtsho

Well-Known Member
There's 2 things AN does right and thats PH UP and PH DOWN. By far the best I've used. It will burn the hell out your skin if it gets on it
AN pH down is just phosphoric acid. You can get a gallon of 85% for $39.95. AN is no stronger than that.

In fact that's basically what it is. AN pH down has 55% phosphate according to their own label.

The most common source of phosphoric acid is an 85% aqueous solution;
"commercial- or merchant-grade phosphoric acid, which contains about 54–62% P2O5"

AN just cost more to put it into a fancy bottle with a shiny label. But all it is is food grade phosphoric acid that can be bought for half of what AN charges. There is NOTHING special about AN pH products.


https://www.amazon.com/Gallon-Grade-Phosphoric-Remover-Clean/dp/B06XZSW3QX/
 

OldMedUser

Well-Known Member
It will work as pH Up but is slow reacting. Potassium hydroxide that is what is in most Up products works a lot faster.

One of the problems people using hard tap water run into is after they pH down and it seems good it tends to rise later. This is because of stuff like calcium carbonate that is slow to react. The pH down takes care of the free carbonate ions right away but them more of the same are freed up and the pH rises. I've explained this so many times that I saved one lecture so I don't have to type it all up again and again.

"I tell guys to run a little experiment. Get a liter or some other amount you know how much it is and check the pH and write it down. Then add enough pH down to get to the level you want and preferably run an airstone in it or at least mix it up a few times for the next 12 - 24 hours then check the pH again. If it's back up to the same as fresh out the tap then you've got hard water with lots of carbonates in it and they are very slow to react with the acid in the pH down. Keep doing the pH down keeping track of how much of that you use the whole time too.

Once you get it to the point where the pH will stay at the level you want and not wander up any more then you will know how much pH down you need to get your water stable and can just add that amount to a batch of water and know it's the right amount to use. Keep an eye on the ppm of your tap water as that will change with the seasons in many places that use surface water as a source so the amount of pH down will have to be adjusted to suit."

Saves a lot of grief to just invest in an RO system or like I've been doing buy RO somewhere but take your pH pen with you and check the first jug you fill as some places rarely change their RO filters and the ppm can be almost like out of the tap. Any higher than 20 I take it up with management.

Minerals in tap water accumulate in the pots so if using high ppm tap water get lots of runoff and/or flush the plants once in a while to get rid of the buildup that can lead to toxic salts buildup and really mess up your grow. If doing hydro then keep track of how much water you add back and do a nute change once you've added back as much as the system holds originally. Not a big deal if it's 100 ppm but many are up to 400+ and that will for sure cause issues down the line.

Tap water can be high in other minerals like sodium, iron, manganese etc that are at levels fine for potable water and may even be good for you to drink but over time, like the carbonates, can build up to toxic levels in pots or hydro systems and cause lockouts or even poison your plants.

Hoping to have my own RO system soon but my tap water comes out of a dugout on my property and needs better filtration and treatment than regular tap water so am hunting down a good source for parts to build my own system rather than something off the shelf. Preferably a local source but not many of those here in northern Alberta.

:peace:
 
Top