Marble Rocks/Cips - Calcium Carbonate

[Salt Must Flow]

Using marble, Marble Rocks/Chips is not something new. There appears to be many more examples of other sources of Calcium Carbonate to buffer the ph so I wanted to show Marble Chips/Rocks in as much detail as I can.

I've been using Crushed Oyster Shell which I purchased at a local TSC store (Tractor Supply Company) suspended in a fine mesh bag to buffer ph of sugar washes for years. It works just fine, but the pieces are so small that it requires a very fine mesh to contain them. Crushed Oyster Shell also compacts pretty dense so I suspect the access to the majority of its surface area is limited. It's common to find 50 lbs for $17.49 or 5 lbs for $7.99 for example.

You can find Marble Rocks/Chips at a local Lowes, Home Depot and likely most other home/garden/landscaping supply company. A 40-50 lb bag cost me $6.38 and is readily available in most areas. You can find nylon net/mesh bags of all sizes really cheap on Amazon. My wife buys tennis balls for our dogs and they come in a nice net bag. These bags are much more open than the fine mesh bags required to hold Crushed Oyster Shell. Since these stones are jagged & irregular shaped, it leaves gaps between them which allows much more access to the surface area of them in comparison to Crushed Oyster Shell. As soon as the sugar wash has completed fermentation I remove the bag, rinse it and hang it to dry.
NOTE: The bag of Marble Rocks/Chips I bought at Lowes needed to be thoroughly rinsed before using for the first time. There was a wet marble paste stuck to the rocks. There were bits of wood that needed to be picked out as well.

Here's some Marble Rocks/Chips in a 1 gallon bucket so you can get an idea of their size. I've been using Marble Rocks/Chips for a while now and they have worked perfectly. I won't be using Crushed Oyster Shell ever again as long as I can use, reuse and find Marble Rocks/Chips.

Just for comparison

[Bradster68]

Great info. Thanks

[Wildcats]

Nice write up SMF. I have been using the crushed shells and just poured them in the bottom of my fermenter. I know putting them in a bag would be easier to separate them out after fermentation is complete.. But I have just gotten used to it. There is a lot of em on the ground around my shed. It would be nice to not have to worry about all the small bits anymore. I will be on the lookout for some of the Marble Rocks like you have. Will make life easier. Thank man. Cheer's

[Demy]

I use marble scraps crushed with a hammer... the size also determines the "reactivity"... the smaller pieces wear out quickly but interact more quickly with the acids but I prefer pieces similar to yours.

[Salt Must Flow]

I use marble scraps crushed with a hammer... the size also determines the "reactivity"... the smaller pieces wear out quickly but interact more quickly with the acids but I prefer pieces similar to yours.

To compensate for the relatively larger size, I just put more in the bag I think I have nearly 1-1/2 gal of rocks in a 50 gal sugar wash right now.

[elbono]

I've been playing with marble slabs, more expensive than the landscaping stuff. Costs about $1/lb but it's easy to deal with. Lean it against the side of the fermenter going in, rinse it off with a garden hose coming out.

What I like is that I learned my old habit of throwing a handful of TSC shells in the ferment isn't that effective. The slabs come out tapered. Thinnest near the surface and not much erosion at the bottom. Seems the most acidity is at the top.

If you use pieces you want them in a bag near the top.

[Salt Must Flow]

I've been playing with marble slabs, more expensive than the landscaping stuff. Costs about $1/lb but it's easy to deal with. Lean it against the side of the fermenter going in, rinse it off with a garden hose coming out.

What I like is that I learned my old habit of throwing a handful of TSC shells in the ferment isn't that effective. The slabs come out tapered. Thinnest near the surface and not much erosion at the bottom. Seems the most acidity is at the top.

If you use pieces you want them in a bag near the top.

That's an interesting observation. I recall reading a post from ShadyLane recently where he recommended suspending the bag at the bottom of the fermenter. I've always suspended it approx 1/2 way just because that was the length of the string. Next time I'll shorten the string and and suspend it higher just to see how it goes. I've been wondering about that very thing lately so I'm glad you mentioned it! I almost considered dangling the bag to the bottom as a test.

[elbono]

I would hang some at different points and see which ones lose the most mass. It's hard to show on a pic but dramatic in person. Every ferment is different the slab comes out 100-300 grams lighter out of 1600 original on 15 gallons. A lively infection eats more (I think).

I sliced a 12x24 tile into three 4x24 slabs. After 3 or 4 ferments two are still in use one came out in one piece but fell apart in my hand as I carried it to the scale. It was 3/8" thick originally but less than 1/8 at the thinnest spot, very porous as well.

I've only played with grain mashes, does a sugar wash act different? IDK

[shadylane]

I'm guessing the amount and how fine or coarse the CC needs to be depends on the water used.
How fast and hot the ferment is going should also be taken into account.

[NZChris]

Use big chunks or large shells and you can just chuck them in and turn your brain off until the ferment finishes.

For example, if I put 12 square inches of thick clam shell into a ferment, by the end of the ferment, the shell may have lost 70-80% of its weight, but still have 9-10 square inches of surface area available to react with the acids in the wash, which is why they behave more like a buffer than a dose of powdered CC of the same surface area.

[Salt Must Flow]

I totally agree with what NZChris just said:

which is why they behave more like a buffer than a dose of powdered CC of the same surface area.

I have bags of powdered Calcium Carbonate. I used to use it when I started out. Mainly because I already had a bunch and it's easy to measure/weight. It kinda works ok, but I found that I had to test the ph every day and add more if/when needed. I kept doing that in order to figure out a pattern/ratio/amount per sugar wash. It just wasn't working reliably for me. I also didn't like knowing I was likely adding more than needed and couldn't reclaim the extra.

Later I started using Crushed Oyster Shells because they just work and are readily available (at least here). They work just fine and you don't have to think about it. I still test ph each day, but that's just for sake of keeping a data log. I noticed that it just worked/buffered, I didn't have to fiddle with adding anything and I was able to reclaim the excess Crushed Oyster Shell after fermentation.

Later I wanted to try using a more coarse source of Calcium Carbonate with a more coarse net/mesh bag. I find Marble Rocks/Chips are a lot more convenient and easy to work with. Cheaper too! I don't mind (and actually prefer) suspending a very large bag of rocks in the wash. It seems to buffer noticeably better than the smaller bag of Oyster Shells. I attribute it to better access to the surface area of the Rocks due to gaps and using a larger amount.

[Biker24a69]

Just added my crushed oyster shells to my 2 big batches one a sugar was one a experiment I'm gonna call shits and giggles
Each mash was 25 gal added 2 cup to each slurry
Wish me luck

[Bradster68]

Just added my crushed oyster shells to my 2 big batches one a sugar was one a experiment I'm gonna call shits and giggles
Each mash was 25 gal added 2 cup to each slurry
Wish me luck

+1 to white marble. I also suspend a few marble size pieces at top of fermenter. Works a charm. Very cool to see them go from smooth to rough after a ferment

[Biker24a69]

Yeah gonna make a trip to hone depot or similar this week to see