Results are in! ACID WATER?

[Ariel]

I've have my Axolotl for a year and a half. She has grown 5-6 inches and seems healthy and happy as far as I can tell.
For the first time today I bought a water testing kit.

My results are
Ammonia 0ppm
Nitrite 0ppm
Nitrate 20ppm

Hooray!

I was pretty confident in my water quality, so I didn't feel a need to test the water until recently. I noticed the smell of the water was different last week, and since I couldn't identify a cause I ordered a testing kit immediately.

The pH of my tank is 6.
Is this dangerously acidic? What causes acid water? What can be done to fix this?

 

[Ammurrica]

6 is not terribly acidic on the ph scale as 7 is a neutral it is just slightly acidic but i believe the reccomendation was 6.8 to 7ish but that could be wrong info i picked up somewhere, you can add things to the water to help with ph but be weary not all of them are axolotl friendly i am sorry i could not help more goodluck!

 

[Ariel]

I know there are things I can add to the water to raise the pH, however, would that be a permanent solution? I imagine it would just cause spikes in acidity and neutrality, I'd really prefer to find the cause of the low pH and fix it, instead of only treating the symptoms. Google seems to say that high ammonia causes a low pH, but when I tested I got 0 for ammonia.

 

[auntiejude]

Nitrate causes acidic conditions, as do tannins from bogwood or IAL. Ammonia causes high pH rather than low.

Have you tested your tapwater pH?

You can try adding a little calcium carbonate to the tank to raise the pH a little, or a calcium tablet - just bundle it up like a bouquet garnis and leave it dangling in the water.

 

[Ariel]

Ok, This is probably not what you meant, but I put an (edible) anti acid tablet in the tank (1000mg of calcium carbonate) in the sand, it quickly dissolved. I tested again today and it worked well, I think.

The pH went from 6.0 to 6.8!
I tested the nitrate also, just because I was curious, and it was 0ppm.
I was afraid that my cycle must have crashed, so I tested Ammonia and
Nitrite, but they were also 0ppm.

The water had not been changed since the last testing of nitrate 2 weeks ago, what makes nitrate disappear?