Growstones - Page 2 - Orchid Board

RJSquirrel · #11 10-31-2010, 04:56 AM

okey

testing this stuff out and let ya know

I noticed today on their website where they list the small size grade as "amended PH for hydroponics"...tried to find what they meant by amended and what with, no luck. Had to look up basic soil PH too...a greater than 7 PH is called basic or alkaline state in case anyone else is curious

Ray · #12 10-31-2010, 09:21 AM

Thanks Izzie. I'm an engineer, so "have to" evaluate stuff. I also like to share info so we can all improve what we're doing. I learn a great deal from others.

RJSquirrel · #13 11-04-2010, 12:41 AM

okey seems no matter what I used the water turned out with a PH rise of .5 to .7

tap water started at 8.0 ended with a ph of 8.5
rainwater started at 6.8 ended up with a ph of 7.5
RJS rainwater paph mix started at 6.2 ended up at 6.8

its on the fine border of being acceptable...

The PH that shot up with the tap water makes it unusable with a high PH.The rest is borderline. It said to rinse the growstones for 45m then discard water. That was the water I used and rinsed each with the water that was being tested

Next I try the rinsed mix to see what we got here.If we still have high PH....

Im mildy disappointed...as I can say at this point the mix is not neutral...I noticed they used "ph neutral" instead of giving you a hard number to kick..hard to knock around an ambiguous number

CTB · #14 11-04-2010, 08:24 AM

We have so much talent on this board, I really Thank-you guys for all the sharing you do. It really makes this a wonderful site.

Intruder · #15 11-04-2010, 05:17 PM

Maybe you can rinse this material a couple of time with a very diluted acid like nitric acid. After a good rinsing with RO water measure the pH of RO water in contact with the material during 24 hours. So you will see if the basicity is superficial or in the matrix. If it is in the matrix it will take a long time to be discarded.

Ray · #16 11-04-2010, 06:21 PM

I really don't know how they can make it truly neutral, in a pH sense, unless they modify the surface to "passivate" it.

"NERD Warning" Skip now if you don't like science.

Glass structure starts with the SiO2 molecule - but is physically set up as SiO4 tetrahedra (picture a triangular-based pyramid, with the silicon in the center and an oxygen at each of the four points). Those oxygens are the shared "links" between the molecules, and they form a really strong and stable network. However, in order for the glass to be useful (pure SiO2 will not even flow at 2000°C), you have to disrupt that network by placing ions into the structure that break those very strong O-Si-O bonds, and the most common and inexpensive way to do that is by the addition of alkaline earth minerals. Most consumer glass, for example is "soda-lime glass" indicating the addition of sodium- and calcium oxides, although there are usually a wide array of additives - aluminum-, magnesium-, and iron oxides to name a few. Those additions all give the glass more of a basic than acidic "flavor".

Izzie · #17 11-04-2010, 06:28 PM

Love it! I'm totally learning about this in Chem right now!

RJSquirrel · #18 11-04-2010, 11:06 PM

you wouldn't think they would add sodium oxide to horticultural grade media..Whatever it is, might and probably is bumping the TDS and EC levels ...ahhh I need meters...scientific tool grade meters

The stones seem great for over waterer's like me I'm seeing bec it doesn't hold enough water to damage a plant BUT it holds enough to keep the roots moist for a few days if you have to leave them.

I put a few orchids with "root problems" already in some and see how they respond. Yeah, I over watered them and killed the roots. Then the plants started to dehydrate bec they couldnt get any water..With this they will have the water they need without drowning or drying out. Maybe pop out some new roots too if they like it.. Nothing lost if they dont. Put a few paphs in it too see how they do.

Very interesting how complex this gets real fast