How pH changes over a 24-period

Below is the textbook theory on how pH changes over a 24-period.

At this point of time, it is actually to point at the end of the day, where the pH should be high. I’m going to turn of the lights afterward, when I’m thinking of doing pH test on my water.

So, I wash the test tube several times with the water from aquarium,

and get 5ml of the water.

4 drops of reagan are put inside, and I slowly shake the test tube to mix the water and reagen.

Oh my. The pH value is 5.5. Doesn’t it mean that after I turn off the lights tonight, the pH level will be going down still? I’m worried.

I have several neon tetras in this tank (that I got from my first tank) for cycling purposes. My neon tetra never swim to the surface of the water, but they did tonight shortly after I turn off the light. I guess not much oxygen left in the water. Lets aerete the water.

That’s the bad thing about fermentation CO2 supply. I can’t turn it off while the light’s out.

Read the rest of the stories relating to this planted aquarium project:

1. Getting things for pilot try of planted aquarium
2. Setting up planted aquarium (phase 1)
3. Setting up planted aquarium (stranded)
4. Setting up planted aquarium (phase 2)
5. Final goods shopping for this aquarium
6. Experimenting with water temperature
7. Installing CO2 system
8. Fermentation started, CO2 bubbles start flowing in
9. More CO2 bubbles
10. Worrying about pH and excess CO2 over the night
11. Getting aquarium cleaners
12. Getting final fishes for the aquarium
13. Plants trimming