Thread: PH of rockwool 7.5

I just cut my rockwool slabs in half, and decided it would probably be a good idea to squeeze the water out of the cuttings to see what the PH of the water inside was... to my surprise its 7.5

I had presoaked my rockwool for 24hours in water with a PH of 5.5



So does this mean I should water the plants at PH 5.0 to make it balance to around 6.5... Or Does the water i give them always have to be 5.8 PH?

Okay

I guess I'm going to water them with water @ 5.5 PH...

I'm still unclear as to how you check the PH of your run-off, or your rockwool... Do you just stick the PH pen into the rockwool? or do you need to rip a piece off and drain it or something?

I just cut my rockwool slabs in half, and decided it would probably be a good idea to squeeze the water out of the pieces I cut off to see what the PH of the water inside was... to my surprise its 7.5

I had presoaked my rockwool for 24hours in water with a PH of 5.5



So does this mean I should water the plants with PH 5.0 to make it balance to around 5.8... Or Does the water i give them always have to be 5.8 PH?


I guess I'm going to water them with water @ 5.5 PH...

I'm still unclear as to how you check the PH of your run-off, or your rockwool... Do you just stick the PH pen into the rockwool? or do you need to rip a piece off and drain it or something?

also i'm very afraid to overwater my rockwool...

^^ Accidental post ^^

I just cut my rockwool slabs in half, and decided it would probably be a good idea to squeeze the water out of the pieces I cut off to see what the PH of the water inside was... to my surprise its 7.5

I had presoaked my rockwool for 24hours in water with a PH of 5.5



So does this mean I should water the plants with PH 5.0 to make it balance to around 5.8... Or Does the water i give them always have to be 5.8 PH?


I guess I'm going to water them with water @ 5.5 PH...

I'm still unclear as to how you check the PH of your run-off, or your rockwool... Do you just stick the PH pen into the rockwool? or do you need to rip a piece off and drain it or something?

also i'm very afraid to overwater my rockwool...

Please don't multi-post. I merged these.
You have to water them wiht the nute solution at the pH you want anyway.
You check runoff where it drips out of the tray. Collect the runoff in a clean sup and test before dumping it back in the res.
Run your system 'dry' for a couple days. Not dry as in no water, but dry as in the nute solution at the correct pH and no PLANTS. Check every 6 or 12 hours and record how the pH changes over time. This will get you used to the interaction of the nutrients wiht the rockwool before adding a third variable, the plants.

Ah sorry about the double post.

and thank you so much for clarifying everything for me.. my head is really starting to get confused, and im starting to feel a bit hopeless..

hopefully i didnt bite off more than i can chew.

The pH of the rockwool is only really important when you are first starting and planting the seed/clone. As you condition it (run your system), the pH will level out. The best idea is to soak them overnight in 5.5 water, then put them in your system and run it for a day like stinky said and see what happens with the pH. If its way out of whack, keep running it until it levels off. Eventually, the rockwool won't have much effect on your pH levels. It's overwhelming to start, but once you get the hang of it, its pretty simple really. Good luck!

Thank you both for the info !

Now I know what I will be doing before I start my next grow...

Unfortunately I suppose I didn't adequately research enough before I planted the sprouts in the rockwool.

I had soaked them in water with a PH of 5.5 for a day and a half, But the system the will be in isn't set up yet- So I haven't had the chance to run it dry for awhile to see how the rockwool would effect the reservoir PH...


I am just hoping that I will be able to balance the PH problems and they will eventually level off, I realllllly hope my babies don't die.