CO2
I read about DIY CO2 in a few places. It suggested radical improvements in plant growth. I decided I'd have a go.
The fermentation bit is really easy. I suggest you buy your supplies, including disinfectant, from anywhere that supplies to home brewers. Use white wine yeast. Various articles call it Champaign yeast. I suspect calling it Champaign yeast is an excuse to charge you more, and in any case, you probably aren't allowed to call in Champaign unless that's where it came from, anyway. The property you want is tolerance to high acidity and alcohol levels, so it will last a long time. I've found 2 and a half cups of sugar and 2 cups of water will last for two weeks with half a teaspoon of yeast. I do the activation in warm water first. See this article.
I inject the CO2 into the output hose using a t-piece: 12mm through, 4mm T. I find the most of the CO2 has dissolved by the time the water gets over the lip of the tank and back down again. I've also used pneumatic bulkhead fittings in the top of the soft drink bottles. These are designed to work well at high pressure: as the pressure increases the seal improves. They are cheaper and easier to buy than other types in UK. I assume that's thanks to steam punks.
The results are excellent for some plants. E.g. on the Telanthera Rosaefolia, each steam produces two new leaves each night with CO2, while it does absolutely nothing without. The Egeria densa produces larger leaves as well. Its beginning to look more like when I bought it again now. Other things are happy either way.
The fermentation bit is really easy. I suggest you buy your supplies, including disinfectant, from anywhere that supplies to home brewers. Use white wine yeast. Various articles call it Champaign yeast. I suspect calling it Champaign yeast is an excuse to charge you more, and in any case, you probably aren't allowed to call in Champaign unless that's where it came from, anyway. The property you want is tolerance to high acidity and alcohol levels, so it will last a long time. I've found 2 and a half cups of sugar and 2 cups of water will last for two weeks with half a teaspoon of yeast. I do the activation in warm water first. See this article.
I inject the CO2 into the output hose using a t-piece: 12mm through, 4mm T. I find the most of the CO2 has dissolved by the time the water gets over the lip of the tank and back down again. I've also used pneumatic bulkhead fittings in the top of the soft drink bottles. These are designed to work well at high pressure: as the pressure increases the seal improves. They are cheaper and easier to buy than other types in UK. I assume that's thanks to steam punks.
The results are excellent for some plants. E.g. on the Telanthera Rosaefolia, each steam produces two new leaves each night with CO2, while it does absolutely nothing without. The Egeria densa produces larger leaves as well. Its beginning to look more like when I bought it again now. Other things are happy either way.
