QUOTE(usermode @ Apr 27 2009, 12:56 PM)
erm..just sharing here sis,
last time when i use DIY co2... each bottle will use 2 cup of sugar + 3/4 teaspoon of yeast. for me, this measurement will last me for about 1 week (by day 6th or 7th, the bubble start slow..so it;s time to make new). i us 2x1.5l coke bottle for every tank. the bubble rate come out is about 2-3bps as using pressurized co2.
the thing about diy co2, the more sugar you put and the less yeast you pour, the longer period of it will bubbling but at the same time, slower/lesser bubbles. just think of it like this for easy metaphore, yeast will eat the sugar and produce co2. so more yeast, more co2 will comeout because so many yeast eating at one time and so produced more co2. but more yeast + more co2, they need more sugar also.. if less sugar, they eat so fast and finish liao. so no more co2 when they have nothing to eat.
anyway, some others have experienced longer period but the basic math is just like that. find tune yourself for the best result that your tank needed (like how much co2 bubbles you need and how long your diy will lasts). just keep doing it and you;ll find the exact measurement for your tank. don;t always follow others in everything because your tank isnt same. use the measurement people give to calculate and make your own to suit your tank. heh...at least you have something to enjoy in this hobby to experiment with rite for starting

totally agree with usermode...
it's depends and u adjust it to ur liking...
like my nano tank....i dun need very high amount of CO2..so slow bubbles is okay for me......
my ingredient will be 1 pack of 500g caster sugar, half teaspoon of yeast and also baking soda.....fill half of the bottle with warm water...i used my house bathroom's heater water...then shake it well....after that continue to fill it to almost full....

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chuppy chuppy chuppy......how how how???my hand gatai d........