I feed my plants by flooding. Then I pump the water out. I use a fresh mix every timer as the food is quite inexpensive. The run off going to my tomato plants
From clones with roots in soil I use a roughly 1/ 3 strength
in veg I use full strength 3-2-1
Full strength
Per Gal
3.6g 5-12-26
2.4g cal Nit
1.2 Epson salts
For the first week or 10 days in flower
per Gal
5.5 g 10-30-20 Bloom Booster
1.2g Epson salts
usually 5 weeks of flower
Full strength
Per Gal
3.6g 5-12-26
2.4g cal Nit
1.2 Epson salts
weeks 8-9
Per Gal
5.2 g 7-15-30
1.2 Epson salts
week 10 plain water
For a full strength for 5 gallon pail it's
18g 5-12-26
12g cal Nit
6g Epson salts
Really all you need is just the 5-12-26 , Cal nitrate and Epson salts
It's what I've been using for years. I just wanted to try the Bloom Booster and Finish as I had to restock.
@AquaTerra has it split into small batches but it's way more economical to buy the 25pound bags and spend $150 for free shipping.
I don't think dry goods go bad unless exposed to moisture. I split the bags into 3 gallon home depot buckets for storage.
I also use it on my outdoor plants and vegetables.
Cheers
CCG