Never flushed before

My plants are 56 days old. They look and smell great. I use OF soil and have used the trio maybe 4 times during their lives. Gradually increasing to the recommended amount. I purchased the sledgehammer and want to flush but I have a few questions.

  1. I have read to use 5x the pot size in ph rinsing water with sledge hammer. My pots are 5 gallons so I will need 25 gallons of water right? So, my plants will be swimming and floating in the much water. What is the best way to administer that much water and how long should it take?
  2. After rinsing what do you do? should I feed them with more water or do nothing ?
  3. Do I keep them in or out of the light afterwards? or any special considerations?

When using the sledgehammer
You mix as per instructions on back of bottle adjust ph as needed
Then you want to run that gallon of mix through soil
I let it sit for 1/2 hour then flush with ph water and stop when run off is clear :wink:
Assuming your in five gallon pots or smaller in larger pits two gallons of sledgehammer mix or more depending on how large pots are


Not sure that I understand you countryboy. Are you saying One gallon mix and then a one gallon rinse?

Don’t I want to try to get the ph in and out the same? One gallon might not do it.

I know that when I use Florakleen with my 3 gallon smart pots, (a product similar to Sledgehammer), I make a 5 gallon bucket of pH’d solution & give the entire 5 gallons to one plant, then follow with a gallon of plain pH’d water; if flushing with only water, I’d give each plant 2 buckets of water each. Do it slow, a few cups at a time, so you don’t disturb the roots too much or cause weird watering patterns in your medium.

What are the directions on the sledgehammer? Mix one gallon of sledge hammer and pH that then water your plant with it you may need 2 gallons of the sledgehammer mix depending on pot size and directions on bottle. Water your plant with that then wait 30 min. Then flush with pure pH water until the runoff is clear then just let it sit and dry out and only pH water after the flush until you harvest

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You will in all likelihood use far less than 5 times the pot size when using Sledgehammer. I use Florakleen and it only calls for a couple of gallons after using. Also; FF does recommend multiple flushes during the grow as their products tend to collect salts.

I used 2 gals on my 7 gal pots

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Well i flushed one of the two plants yesterday. Man, it takes a long time. I used one gallon of flush and five gallons of rinse. I brought the PH from the runoff from 5.8 to 6.1 and i.m going to leave it there. The plant looks fine this morning.
What do you all think? I need to flush the other one today.
Should I feed them after a day of rest or when do I start because there are no nutrients left in the soil?

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I flushed the other one the same way with the same results. Ended up with 6.1 run-off on both. I gave them a day to rest and dry a bit. Then gave them 60% nutrients this morning. we will see what happens.

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I usually let the soil dry out for a complete wet to dry cycle after flushing and before adding anything else just to let the roots dry out.

well i did the way I did it. Looks ok so far. I’m learning.


We’re all learning! :blush:


I have the same question, wish someone could answer. I do not believe I can put 25 gal of water thru a 5 gal pot without drowning the plant. Are we talking over a week month year day hour cant comprehend it. Please explain how this is done!!!

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That’s where sledgehammer/florakleen help. They reduce how much you have to run through when flushing. With sledgehammer, mix up a gallon of water with sledgehammer, slowly pour that into your pot. Let it sit for 30min-1hr to let it absorb the salts, then run another gallon or two to wash out the salts and sledgehammer. Do this all in one day.


I would take mine out in the yard and run a garden hose for 30 minutes then pour 2 or 3 gallons of R/O over the top afterwards. 7 gallon cloth pots.

I get great results now with Florakleen and R/O water.

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