Correcting PH in Grodan sugar cubes

McFrosticles

Well-Known Member
I'm growing 7 plants in 12 litre buckets filled with grodan, but probably filled with 10 litres of medium.

Watering with nutrient solution PH'd to 5.5/5.6. Tonight's watering I poured 18 litres through each bucket and had to stop as it takes so long doing it all by hand. So about 125 litres of solution with 70 litres of run off gave me a PH run off of 6-6.1 in each bucket

Can I drop the PH of the nutrient to say 4.5? or does it not work like that?

Also I cant find any info on how to calculate run off, I know it should be 10-30%. Is that volume of the whole pot, so a 12 litre pot would have 4 litres run off?
 

JDMase

Well-Known Member
I'm growing 7 plants in 12 litre buckets filled with grodan, but probably filled with 10 litres of medium.

Watering with nutrient solution PH'd to 5.5/5.6. Tonight's watering I poured 18 litres through each bucket and had to stop as it takes so long doing it all by hand. So about 125 litres of solution with 70 litres of run off gave me a PH run off of 6-6.1 in each bucket

Can I drop the PH of the nutrient to say 4.5? or does it not work like that?

Also I cant find any info on how to calculate run off, I know it should be 10-30%. Is that volume of the whole pot, so a 12 litre pot would have 4 litres run off?
You can drop your input pH down to equalise your medium pH but I wouldn't do it so significantly. Now you're at 6 run off I would water my next watering with 5.8 and test run off after that.

Sounds like a lot of watering. You'd do better to get a reservoir and a dripper system.
 

McFrosticles

Well-Known Member
You can drop your input pH down to equalise your medium pH but I wouldn't do it so significantly. Now you're at 6 run off I would water my next watering with 5.8 and test run off after that.

Sounds like a lot of watering. You'd do better to get a reservoir and a dripper system.
Thanks, I wish to god I had looked to automate before I started lol, hand watering rockwool is no fun
 
Top