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๐ฟ Master your grow with precision pH power!
Humboldts Secret pH Down is a 32-ounce concentrated phosphoric acid liquid designed to rapidly and precisely lower pH in soil, coco, and hydroponic systems. Its potent formula ensures optimal nutrient absorption by maintaining pH between 5.5 and 6.5, promoting healthier, stress-free plant growth across all mediums. Trusted by growers, it delivers professional-grade results with minimal use, supporting stronger roots, vibrant foliage, and higher yields.












| ASIN | B0BW3G96VV |
| Best Sellers Rank | #36,771 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #1,032 in Garden Fertilizers |
| Brand | Humboldts Secret |
| Brand Name | Humboldts Secret |
| Coverage | Medium |
| Customer Reviews | 4.6 out of 5 stars 456 Reviews |
| Item Form | Liquid |
| Item Weight | 2.58 Pounds |
| Liquid Volume | 32 Fluid Ounces |
| Manufacturer | HS Supplies, LLC |
| Mixing Ratio | a few drops per unit of nutrient solution |
| Model Number | HS-PH-DOWN |
| Number of Items | 1 |
| Number of Packs | 1 |
| Specific Uses For Product | Plant Growth |
| Target Species | plants |
| UPC | 706199757427 |
| Unit Count | 32.0 Fluid Ounces |
J**.
It works fabulously
I've been doing hydroponic systems for over 20 years and this product works better the any ph down I've used.
R**H
This stuff is great!
The pH on my cannabis plants was at about 7 1/2 almost 8. They were not taking up nutrients like they should, which is obvious by their stunted growth and within one water and using pH down itโฆ Problem solved! Perfect, 6.7 PH. All I did was mix my feeding solution take the pH, Then add pH down until the pH was at around 3 1/2 which I figured is half of the approximate 6 1/2 I was looking to get. And it got me there right on the line. The only problem with this product is there are no real directions. You kind of have to do trial by error and let me tell you folks please err on the side of caution. This is straight acid that will definitely burn your plants so do not apply this directly. Do not apply this in high doses. I would say start with a cap full in a gallon of your feeding solution and then go from there, adding more until you get to where you want to be. That said, I kind of understand why the directions are the way they are because every solution is a different pH, so there is no perfect amount. Itโs always going to be based on your water quality and the pH of your nutrient base. At any rate, I will tell you that this product works absolutely great. I would avoid getting it on the plant itself and apply only to the soil. Happy growing.โ๏ธ๐โค๏ธ๐คฉ๐ฑ๐ณ
B**6
Yep
As promised
S**N
Lowers Ph.
I use this to lower the Ph in my water prior to watering my plants.
R**N
Humboldt ph dn
Works great and I use less then other brands per feeding
E**O
It's ok๐คท
Good size for the price but PH is very intense and you could find yourself measuring back and forth with no measuring devices
D**O
My go-to
Lowered my PH just like it said it would.
P**L
carful
I don't know what kind of Acid this is. I am not sure its legal. I tried a ph tester (cheap) and it pegged 00.00. not sure if my tester is to cheap but the point stands. STRONG
G**Y
It's better to get this big 1 it works better than the smaller bottle.
Perfect for plant health and it works for meny grows .
Trustpilot
3 weeks ago
4 days ago