Jack's ClassicNutrients Hydroponic 5-12-26 Professional Fertilizer Part A, 25 lbs

Least expensive, for great results

Jack's is all you need to grow great crops. I doing Jacks 321 in dwc in RO water.. Part A, Epsom Salt, and Cal-Nit. This stuff works so well that I bought big 25lbs bags. For about $200 bucks I have enough nutes that will last a small/hobby grower, like myself, many years. I only run about 800ppm max in flower and I run at least a 7 day flush of ph adjust RO water before harvest. I have no issues starting seedlings and clones directly in 300ppm of 3,2,1. I do add ph up powder to the mix to get it up to 6.0ph since I use RO water.

But since I've used it for so long I know the best mix that my garden likes. I don't use it for hydro, but for an outdoor garden and tweak the calcium nitrate to where each group likes and add extra nutrients for other plants that require it.This big bag will last me a few years since the garden isn't huge. Gotta vac seal the unused portion to keep it from absorbing moisture or the water will ruin the measurements.

Jacks is my reccomendation. Stuff is cheap and works like a charm. My plant health is always perfect. I don't use bloom boosters and I'm bring home bigger crops than I was with more expensive line ups. Jacks 321 is where it's at.

This is my go-to Part A fertilizer, even for hydroponics. Dry fertilizers are always a better value than the liquid in a bottle counterpart, and give you more control over your mix. Make sure to get the Part B and C fertilizers to maximize the potential of the fertilizer, and to find out what amount you need for your specific usage. The price tends to fluctuate a lot, and ends up being over $100 in the Summer, so it may be worth stocking up in the Winter when people are using fertilizers less. Even if the price is around $100 however, you're still going to be saving so much money compared to the alternatives.

I’ve used the Jacks 321 formula for years.Simple and reliable.Makes my autoflower plants look like photos.They grow great!

Great fertilizer

Had holes nutrient spilling out and box was beat up by Mike Tyson