Edward

Personally, I am not sure if the CO2 tables we use are correct. After spending years chasing KH, CO2 and pH I found easier way. No KH buffering, no pH testing and no sick fish and plants. Actually, fish are much happier and plants grow even healthier. The plant list includes several dozen plant species from Echinodorus and Cryptocoryne to Wallichii and Toninas. Never had a plant that wouldn’t like it. Lower the KH nicer the plant.

Fish I have are Tetras, Angels, Altums and Discus, naturally soft water fish. Brackish and Tanganyikan Cichlids are not compatible of course.

Generally fish don’t like pH changes and high CO2. The actual pH doesn’t matter. CO2 is natural to the fish. It creates stability at pH ~ 5.6. It never goes bellow 5 or so. (As an experiment I added peat moss to lower it even more, bellow CO2 capacity of 5.65 to 3.7 and still no problem)

We can not stress more the need to use CO2 only. No other acids are safe.
If you see your fish in stress or dead then it is due to high CO2, poison or non CO2 acid.

Can you define such crash?
What we see is CO2 overdose not pH crash. It is the CO2 killing the fish not the low pH.

Tropical rainy season removes carbonates (KH) buffering and takes large amounts of humic and carbonic (CO2) acid. Are there casualties because of some pH crash? No.

We shouldn’t be afraid exploring more natural approach growing fish and plants in our aquariums.


Thank you
Edward

hoppycalif

Great post Edward! Your explanation fits all of the facts I know of. You say you don't think the pH/KH tables give good numbers for CO2 - I agree with that. How do you measure or estimate how much CO2 you have in the water?

Edward

Thank you hoppycalif
Not knowing the CO2 level worried me for some time. When everything was growing well I couldn’t test it due to the KH being at zero. One dose of baking soda exposed the probable CO2 level of 10-15 ppm. This was enough under high light 6 Watts per gallon PC.

Here are the CO2 rates:
10 gall => 10 bubbles / min
50 gall => 50 bubbles / min
100 gall => 100 bubbles / min

I would like to add that tiny aeration is beneficial when fish is in the aquarium.


Thank you
Edward

banderbe

That's interesting, I bubble 180 bubbles / min into my little 29 gallon tank. No leaks either as I just use a limewood airstone and can pull the tubing and see the bubbles coming out of the tube into the water. Even when I was using a reactor I had to push that much CO2 in order to get the one point ph drop.

Edward

What was your KH?

banderbe

My KH used to be 18.. now it's 3.

Either way I had to put the same 3 bubbles / second into the tank.

Krisybabe9

I like the idea and the information that you posted.
I'm interested in giving it a shot.

I currently buffer with baking soda. How would I go about making the change in such a way that avoids fish stress? Anytime I try to reduce the amount of buffer I add my fish gasp at the surface.

Glouglou

What is "pH crash?" Simply, this is when the buffers in your water are all used up and the pH of the water plummets. This is not good for the tank inhabitants or the biofilter. Many of the nitrifying bacteria are inactive at a pH below 6.0.

It happen to my tank and my Hagen KH test at this time show around 1 mg/l.

My Ph went to around 5 in matter of hours.
Liquid CaCo3 was administered, no fish loss.

I was working with Hagen CO2 system at that time, I, only in rare occasion manage to have around 20mg/l of CO2.

Edward

All of my 13 aquariums don’t have any pH buffers and KH and still, I never see any fish gasping for air. All tanks run CO2.

What kind of fish do you have?

Bert H

Edward, help me understand here. Are you saying that in your opinion/experience the actual pH is not important (as long as it doesn't drop below 5), but stability is the important factor? A bubble rate of approx 1 per second in your 50 gives you a pH of 5 and fish and plants are happy?