PPK question - anyone try lava rocks as medium?

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tilopa

Member

• Jul 24, 2020

• #1

I'm wondering if lava rocks would be a good medium for PPK. I'm talking about the 1/2" size light porous red volcanic rock. It is very air and conducive to supplying more oxygen to the roots, but I question whether it has much wicking ability?

I liken it to hydroton which does not wick very well.

Side question, what size buckets do people use in veg. If say you are using 5 gallon buckets for flower, what size would you veg in?

 

Frosty Nuggets

Well-known member

ICMag Donor

• Jul 24, 2020

• #2

I'm not sure what PPK means but I used lava rocks as medium about 25 years ago and it worked well.

 

PetFlora

Well-known member

ICMag Donor

Veteran

• Jul 24, 2020

• #3

Although I used lava rock successfully, it broke down and was messy to clean up


I moved from there to polished ornamental stones, which I have used for years. Not only do they work great, they are easy to clean and reuse, but I came across Bright Water Medium and am experimenting with it this grow. It's coarse ceramic hollow extrusions cut into 1/2" pieces, plenty of surface area for delicate roots to attach to

 

T

tilopa

Member

• Jul 26, 2020

• #4

PetFlora said:

Although I used lava rock successfully, it broke down and was messy to clean up

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Interesting, the lava rocks I'm talking about are very hard, yet light an porous. My neighbor uses them on his walkway.

PetFlora said:

I moved from there to polished ornamental stones, which I have used for years. Not only do they work great...

Click to expand...

I would think that polished rocks would not wick very well?

 

PetFlora

Well-known member

ICMag Donor

Veteran

• Jul 26, 2020

• #5

tilopa said:

Interesting, the lava rocks I'm talking about are very hard, yet light an porous. My neighbor uses them on his walkway.


I would think that polished rocks would not wick very well?

Click to expand...

I know, but the ornamental rocks are different sizes and shapes and the roots grow all around them

 

Klompen

Active member

• Jul 26, 2020

• #6

The type of rock you're likely referring to is known as "scoria". Depending on where it is from, it can have rather high salt levels in it. A good flush or two or ten is always a must.