Adding CO2

Beautiful catfish you have there!

CO2 added to the water doesn't stay there. It is constantly lost from the water surface, so a few hours later the amount in the water is back to near what it was before you added some. That is true no matter what the KH of the water is, and no matter what else you add to the water.

The baking soda some people add to their DIY CO2 generator is just to keep the yeast/sugar/water solution from becoming too acidic for the yeast to grow. It has no effect on the CO2 in the tank water.

 

A single DIY CO2 bottle is extremely unlikely to generate enough CO2 to kill your fish. If you get a drop checker and fill it with 4 dKH distilled water and a couple of drops of pH reagent, the water in it will be green when you have about enough CO2, and very yellow when you have too much.

 

I don't know what the amount of bicarbonate of soda needed is. But, if you have a KH test kit, that isn't too old, you can check the KH after you mix it, and verify it yourself. You don't need absolute accuracy. If it is between 3.5 and 4.5 that is fine for use in a drop checker.

 

Baking Soda is different to Bicarb!!!! Need to make sure you get Bicarb.

I made mine adding 6g Bicarb to 5ltrs DI = 40dKH
10ml of 40dKH added to 90ml DI = 4dKH

Making the first solution so large and then taking a little of it to make 100ml of the final solution means much less room for error/variation.

i.e. If you were to add 0.6g to 500ml and were 0.05g (8.33% error) out then it is less accurate than being 0.05g out on 6g (less than 1% error)

AC

 

I think I'd add more plants or let the cycle complete entirely before adding fish...just to be sure

 

In the United States baking soda is sodium bicarbonate. Perhaps you were thinking of baking powder, or maybe it's just a nomenclature difference between countries.

 

By the way, this almost gave me a heart attack. I thought, "Oh my God, what have I been adding to my tank?" As the poster above states, this is not true for Arm and Hammer baking soda, at least here in the US.

 

As far as I know, as long as the solution is mixed using RO water, making a 5dKH solution will only change the color at which 30 ppm (or any given concentration for that matter) is indicated. For RO dKH solutions the pH/KH tables are reasonably accurate. I think people use 4dKH cuz at 30 ppm or so it's green to yellowish, and that's an easy color to see and differentiate, instead of, say dark blue vs light blue.

 

No....we use 4dKH because Tom told us all to

I think its the green thing really like you said

Ac

 

Ouch!