What rate of CO2 di I set?

[andrewcollier]

I have a 400 litre tank with a Denearle CO2 kit and I am shortly to get it fixed up with a pub size cylinder. What rate do I set the bubbles at? Many of my plants are looking very sad, how long should I expect an improvement?

Also I have just been reading on this site about KH. I have not heard that mentioned before but it sounds very relevant.

All comments appreciated

[phanmc]

Start off at around 2bps and wait for a couple of hours until the CO2 test kit can calibrate, then increase or decrease the bubble rate as needed.

How much light are you working with? Improvement depends on light level, available nutrients, and types of plants. In general, you should see improvements in a week.

With the CO2 test kit, you don't need to worry about the kH.

[andrewcollier]

Thanks for the reply.

The lights are on for 10 hours a day and I have kept them to that since 30-09-07 when I removed the reflectors and bought my last plants from Greenline. I have a Juwel Rio 400 with new tubes. system started June 07.

All plants purchased from Greenline were for below average light. I have added Greenline food pack.

Before my current stock I had a big problem with Algae (Black beard!) which so far has not returned, so I don't want to increase the light to propagate it.

My tank is at capacity for fish and I do weekly water checks (consistently OK) with 20% water changes. Just had a bout of white spot, so water quality may not be as good as it should be.