Hi.

How do you know what rate of CO2 bubbles is needed in your tank? :-?

The best thing IMO would be to invest in a CO2 test kit(Sera have one).

The rate of CO2 injection is then based on the reaction(colour change) in the test chamber.

Cheers

Glenn

I have one...

So just make sure it is in the safe colour zone?

Yep. Start off in the blue and slowly increase to green.Yellow is to much CO2.

Cheers

You can work it out by the difference between your KH and pH. I also made a DIY bubble counter.

One of these is a useful and reassuring investment...

http://www.dse.co.nz/cgi-bin/dse.storefront/45a1b6ba01693794273fc0a87f33071f/Product/View/Q1416

Those CO2 test kits are really only pH indicators and not terribly sensitive at that.

When your fish start gasping at the surface (and there is SOME surface disturbance) thats too much.

If your pH drops more than .2 thats too much, or you need to increase the kH (I use a handful of coral sand).

I'd start at 1 bubble per 2 seconds, then start cranking her up a little each day. Actually thats a lie, I'd start at a bubble a second, but thats not safe advice.

Another good way to raise KH is sodium bicarbonate (NaHCO3 - aka baking soda not baking powder... ); as a rule of thumb - 1 tspn, or about 6g, should raise the KH of 50 litres by 4dKH. Best to make all water chemistry changes slowly over time and be aware of what your local chemistry is like.

I don't buffer my water or test pH/KH

I use the method described in this thread: http://www.plantedtank.net/forums/gener ... thout.html

Seems to work well.

Another way to protect your fishes and keeping your plant healthy.

I am sure some of you guys uses Solenoid. it is definately a useful device that cut out the co2 when the light is turn off.

My co2 is turn on only for 8 hours. this will help to keep my plant healthy. (CO2 is just one aspect of keeping your plant healthy).

I know for sure that if i was to left it on at my setting rate for 24/7. my fish will be in heaven.

To me solenoid mades a lot of different.

Interesting Plant man, but I leave my CO2 on 24/7 and my fish don't go to heaven..

It depend if you are using a DIY system or pressured system for your CO2.

At one time, i have four DIY canister going on for 24/7 in a four footer tank (fully planted tank) and the fish is still good.

The rate i am settign is very high. 5-6 bubble per second in the bubble counter. at this rate, the fish will be at great risk. The solenoid will eradicate this risk. This rate also depend on your lighting strenght, fertiliser, the size of your tank and how much plants is in the tank.

But with the solenoid, the CO2 is not wasted and will be consume by the plant when the lighting is turn on and the fishes are save.

So far, it work for me.

Also depends on how you diffuse it. With a standard ladder or spiral you can never OD on CO2 as it just wont absorb enough. I recommend using small filters to diffuse the CO2, it works a LOT better, so much better that the word 'lot' deserved the bold and italics given to it.