see link...that's all i know.

Here is a link that might be useful: tea bags posts

Just seems like any material can do the job so long as it allows good flow of water. A mesh bag will do the trick but you'll have to dunk or stir it to mix it up. Much simpler to aerate (aquarium air pump and air stone) and just add VC. The action of the bubbles should be good enough flow around the container you are using.

Try cheese cloth it's made of cotton, is easy to work with and cheap, you can find it in food stores and some dollar stores. The stuff is tougher than it looks. I use it for a spice bag in hot pickle solution and it holds up for that. Good luck on your idea.

Curt :-)

I would use a sewing machine and recyle old bed sheets and tee shirts

I myself use an old sock

I get ladies nylons (Ones w/ runners or tears) from the women in my life. Fill the foot and it works great!

I didn't reply before because I knew I'd be a downer. I've already done this homework in detail.

To sell: Purchase bags and fill with castings. Cotton. You can't make them cheaper than purchasing them in bulk. Selling was the point, right? Not just personal use. Kinda knocks out many other suggestions if you want someone to actually buy them.

Recycling is noble and I suggest if for personal use or if you don't care about making money of the venture. However, you won't make money off it unless you are just super fast at it or you have something innovative to offer that GREATLY increases value to your customer. I have recycled t-shirts and such. The time it takes to make the bags at home with a machine would require a much higher price to turn a profit and pay for your time, machine, supplies, and maintenance than what most people are willing to pay.

What is your time worth? Let's say $20/hr minimum, especially since there are no benefits in this (401k, health coverage, worker's comp if you get hurt, unemployment insurance, etc). Time yourself making the bags. If a bag takes you 10 minutes to make, including the time to scoop in the castings cleanly since not everyone wants to directly touch worm poop, you have to charge $3.33 for the bags just to cover time. And that is if you don't screw a single one of them up. Not to mention the other expenses (supplies) and potential profit. Is a spot at your farmer's market free? Some are, some aren't. Once you do the math accurately, is it going to pay off?

Tie a knot in a sock and call it a day!
Use old crew socks and rubber bands to close.
Fill it with castings and make tea.
Case closed...Next?