Has anyone has success with Growstones?

[hypostatic]

So I've been doing some research on Growstones and their suitability for SH culture, and I was wondering if there was anyone out there who has actually tried using it, and what were your results with it?

[DTEguy]

Originally Posted by hypostatic

So I've been doing some research on Growstones and their suitability for SH culture, and I was wondering if there was anyone out there who has actually tried using it, and what were your results with it?

I got some free samples from a local hydroponic store and did some dry runs with them. Here's a list where you can get some free samples:

http://www.growstone.com/wp-content/...f-from-Pat.pdf

There are two sizes; small and medium. The small wicks but too much in my environment and also too compacted. The medium size wicks just right for me. However, the media (even after thorough cleaning) brought the fertilized-water pH up from 5.5 to 7.2 overnight. I haven't tested it with any orchids.

There very very light and floaty....but can be held down with a layer or rocks on top.

Please keep us posted if you test it out with actual plants.

[hypostatic]

Hmmm yeah, I've read about the potential pH issue.

Would there be any way of easily fixing this, like soaking the media in a buffering solution?

---------- Post added at 02:04 PM ---------- Previous post was at 02:00 PM ----------

I'm particularly interested in the grwstones because they seem to have better wicking capabilities than standard LECA (from what this video shows)

Grow Stones Grow Media For Use in Hydroponics Systems - YouTube

[DTEguy]

They claimed that the stones are coated with buffering agents and soaking it overnight will bring down the pH. I did that and then rinsed thoroughly and soak with adjusted MSU fertilized (which is basically also a buffer) water overnight. The pH still rises.

Bear in mind that the stones were immersed in fertilized water and the stones in S/H might even raise it higher/faster (I think).

Perhaps the pH issue can be overcome overtime...but I don't have the knowledge to confirm that.

[hypostatic]

From their website:

How To Prepare Growstones For Hydroponic Use

Below are simple recommendations for best results.

Preparation Instruction

For first time use, rinsing is necessary to eliminate any dust created during shipping.
Poke small holes at the bottom of the bag. Open the top of the bag and insert a garden hose. Drain.
Place Growstone in your hydroponic system with pH-corrected nutrient solution.
For best results adjust pH to 5.5 – 6.5.
You are ready to Grow!

What does "Place Growstone in your hydroponic system with pH-corrected nutrient solution" mean (sorry I'm really new to all this)?

[DTEguy]

It means to adjust the pH of the fertilizer solution to that range, your fertilizer acts as buffer--stabilizing pH and resisting change.

Which means you will need to measure the pH (electronic pH pens or color strips) before you add a pH adjustment solution.

I use lemon juice to bring mine down...too much work to squeeze fresh lemon

Edit: Come to think of it, perhaps the reason why my pH rises quickly in growstones is because lemon juice is a weak acid. You should check with your store for a better pH adjustment solution.

[Ray]

Growstones are made from foamed, remelted soda-lime glass. Such glass formulations predominately utilize Na- and Ca-bearing minerals to flux the silica, although there is bound to be B, AL, Mg, K, and any number of other ions in the mix - especially considering thyey use recycled glass, so cannot have a real tight grip on the chemistry.

Because of that, the glass will be basic in its chemistry, so will "overthrow" whatever solution chemistry to which it is exposed.

In active hydroponic systems, that will be less of a concern, as they usually include automatic controls to adjust the chemistry. It's simply not the same in passibe hydroculture like S/H.

Frankly, being a ceramic engineer and scientist, plus a big believer in recycling, I would LOVE for their materials to be good for us, but in my testing, I see the same results as Yang, so have discounted the concept for the time being.

[hypostatic]

Hmmm, is there a similar foamed inert plastic product that exists for S/H purposes? Like packing peanuts or something?

Also, what about small rockwool cubes?

[Ray]

The trouble I have had with rockwool is that the cubes become individually saturated, so exclude all air penetration, and over time they compress like sphagnum - mostly from top watering.

Plastcs tend not to wick very well.

[hypostatic]

Hmmm, I see.

So just out of curiosity, if the growstones were made out of regular glass (not soda-lime glass), would it be more pH neutral, and still have the same properties?