ssj4jonathan
Well-Known Member
I've been using growstones gs1 in a modified waterfarm hydro setup for a little over a month now and would like to share my "expertise" on this medium to help others who are thinking about using this product.
The good: the medium absorbs a nice amount of water, and holds it for about a day or two given your ambient temps. It's light weight and is really good at trapping air. Roots are able to attach themselves to the crevices of the rock and grow nicely.
The bad: it floats when flooded. It is continually shedding sand/grit. Another con is this medium is very abrasive. So don't mess with the root ball once your plant is established, or otherwise expect lots of mangled roots.
The ugly! I did a bit of research and have found out growstones use calcium carbonate as a foaming agent with concentrations ranging into 5% per weight. This translate into a never ending battle of pH spikes of 8 plus. I've been trying to get this medium to pH stabilize for the past month with very little success. Instructions given do not work. Tried soaking in 5.5 water over night to find out pH has risen to 7.8. I've resorted to using sulfuric acid pH'd to 3.0 to neutralize all the CaCO3. This product is not pH stable by any means out of the bag. The stones themselves are a great medium but when loaded with calcium lime, they become useless. DO NOT use in your hydroponics system until pH balanced to 6.0. Hoping my last 3.0 treatment will stabilize the ph. So far I've used about 100 mls of lead battery strength sulfuric acid, which I believe is 33% pure.
The ugly part about this medium will prevent me from buying it again. At the same time once I get my current batch hydro stable, I will be reusing it till it all disintegrates. Theres definitely a love hate relationship going on using growstones
The good: the medium absorbs a nice amount of water, and holds it for about a day or two given your ambient temps. It's light weight and is really good at trapping air. Roots are able to attach themselves to the crevices of the rock and grow nicely.
The bad: it floats when flooded. It is continually shedding sand/grit. Another con is this medium is very abrasive. So don't mess with the root ball once your plant is established, or otherwise expect lots of mangled roots.
The ugly! I did a bit of research and have found out growstones use calcium carbonate as a foaming agent with concentrations ranging into 5% per weight. This translate into a never ending battle of pH spikes of 8 plus. I've been trying to get this medium to pH stabilize for the past month with very little success. Instructions given do not work. Tried soaking in 5.5 water over night to find out pH has risen to 7.8. I've resorted to using sulfuric acid pH'd to 3.0 to neutralize all the CaCO3. This product is not pH stable by any means out of the bag. The stones themselves are a great medium but when loaded with calcium lime, they become useless. DO NOT use in your hydroponics system until pH balanced to 6.0. Hoping my last 3.0 treatment will stabilize the ph. So far I've used about 100 mls of lead battery strength sulfuric acid, which I believe is 33% pure.
The ugly part about this medium will prevent me from buying it again. At the same time once I get my current batch hydro stable, I will be reusing it till it all disintegrates. Theres definitely a love hate relationship going on using growstones
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