Correct way to flush using FF Sledgehammer

I am fairly new as well and growing in a greenhouse. I have 4 WW photos and one Gorilla Glue Auto not yet harvested. The other two are curing. I have the additional issue with heat, 105F somedays inside and it has played havoc with my Growing and learning. The photos are in a 50/50 mixture of HF/OF soils. They are hot and you don’t feed for weeks. My PPM numbers stayed very high 2500-3000 after 2-3 months. I tried a half assed flush, 3-4 gallons per plant to no avail. best i can tell, I had nutrient lock, even though I had fed them very little and heat stress didn’t help them either. Some weeks I was watering daily, 2+ gallons per plant but leaves looked terrible. I was properly schooled on flushing finally. The simplest way, if you can do it, is to just run water until the PPM’s come down to your desired number. I ran almost 25 gallons per plant, and finally I saw numbers I had not seen before, as in 3-400 PPM’s. Now I feed, then water next time and they are already hungry again. All their new growth looks fantastic, no burns, deficiencies. I have SledgeHammer but forgot to use it, lol

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i was really hoping i wasnt going to do that much water but thanks for telling me. time to drown my plants i guess

Well I have the greenhouse, so water is not a problem. indoors it can become a challenge.

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And my plants were in pretty bad shape, so more than likely you won’t need nearly that much to get your numbers right

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i have a concrete floor with a drain in the middle so i just roll them over and they drain out. mine look like they are struggling hard so i am going with what you said.

I forgot to add my tap water runs around 500-550 PPM’s, so feeding was a challenge as well since you had to account for that even if the plant didn’t use most of it. I would flush as close as you can to your tap water readings, assuming you are using tap water, with PH corrected water. I used 5Gal buckets so it is easier and quicker to PH compared to gallon jars. I now have an RO Buddie RO System, just over 60 bucks at Amazon, and my PPM’s run around 5. Guess what! I was starving them and had no clue. I am feeding them 1300-1500 PPM’s and next day when watering, the numbers are already down to 6-700. The 4 Photos are 8-9’ tall and eat a lot. I have been starving them for quite a while now with the nutrient lock and the heat. Glad I learned before destroying them

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i have a carbon filtered water system that takes out the chlorine and the ph reads 7 so i dont stress if i have to water once or twice but i just figured out my problem i am now the official bonehead of the day. i raised my lights as far as i could. they are on the ceiling joists. the plants got too tall and the light was running full bore! the damage is not on the bottoms!!! i baked my plants

Just checked ff web site. They say: use 2x the amount of water you usually use to feed add 2tsp of sledgehammer per gal and apply. Wait till top 2/3 inches are dry before feeding again.

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i am dumping ff. i am going to jacks for my next grow. i have a whole shelf full of NFTG that i was using on my outside plants and i think i will just finish up with this stuff. i have 2 in jars, 1 hanging, 1 a week away from harvest and 5 about 2 weeks out and 2 blueberry that still need nutes plus the 6 zkittles all about to be NFTG babies

I got the same directions.
I’ve contacted Foxfarm multiple times to get the official process to use Sledgehammer.
They insist you only apply the solution into twice the amount of water you normally use. Let it dry and go back to normal feeding schedule. No rinsing / flushing it out.
But most growers insist you should rinse it out with lots of water. Everyone has a different opinion about the amount. I’ve heard anywhere from 1 to 20 gallons.
I’m going to follow their instructions and see what happens. Pray it doesn’t hurt them.

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I’ve got to believe since they made this crap I’m gonna listen to them. I’m about due (next dry out) for my 1st flush so I’m doing it their way.

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I think the purpose of the sledgehammer is to use less water . Foxfarm Instructions make sense to me by allowing the solution to do its job and break down the salt or whatever. And on your next watering or feeding it kind of rinses.

I had tried it this way once and the plant did not like it one bit. It wouldn’t uptake the water with the sledgehammer. A plant that would normally dry up every other day took 10 days to dry out. By that point the damage was done. It could have been the strain because blueberry autos are picky bitches but haven’t done it that way since

I tried doing it FF way on one of the plants a couple days ago.
Today it doesn’t look too happy.
I talked to someone at FF and suggested they put more detailed instructions on the container.
It’s a soapy solution that I can’t imagine the plants would like to soak up.
Personally I think somewhere in the middle is best.
Letting it sit for an hour to do it’s thing and then rinsing it out with 1 to 2 gallons of water
Just my humble opinion.

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That’s how I’ve always done it. Pour in sledgehammer, let it sit for 30min-1hr. Follow with as many gallons as it takes to get to the ppm level I’m looking for then finish with a gallon of feed. Never had issues doing it that way.

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2 days after flush

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