Co2 And Low Ph

Hi,
I have a 20 gallon tank which I cycled not too long ago. I recently added diy co2 and my ph went from 7.4 to 6.5-6.6. Ever since I added co2, ammonia been appearing to about .5ppm and I've been doing 25% daily water change. I heard that BB would go dormant if my ph is low. I have 5 fish and they seem to be doing fine. What should I do and should I be worry?

ph 6.5-6.6
nitrite 0ppm
nitrate 5ppm

 

Since no one has chimed in yet, I'll give it a try. From my knowledge of the human body, dissolved C02 in the blood causes it to go acidic, so I would imagine the same applies here. Your pH isn't that low but maybe hold off on the C02 if you're really worried. The most important thing is that you don't allow the pH to fluctuate. What fish do you have? The only problem I would see here is the ammonia, which I can't see being the fault of the C02. I have no experience with c02, so this is inference by knowledge have gathered.

 

Since no one has chimed in yet, I'll give it a try. From my knowledge of the human body, dissolved C02 in the blood causes it to go acidic, so I would imagine the same applies here. Your pH isn't that low but maybe hold off on the C02 if you're really worried. The most important thing is that you don't allow the pH to fluctuate. What fish do you have? The only problem I would see here is the ammonia, which I can't see being the fault of the C02. I have no experience with c02, so this is inference by knowledge have gathered.

Thx for the reply, I took my c02 off a while ago to see what happens. I have 3 neons and 2 sterbaI cory. I had a bad batch from petsmarts. I was planning to get more from a lfs but I decided to stop since I was having a ammonia reading. Guess they have to be lonely for a couple more days

 

Do you know your ammonia reading now? Has it gone down any?

Have you tested your tap? Sometimes ammonia can source from there

 

Have you tested your tap? Sometimes ammonia can source from there

0 ammonia from tap

 

Well if it isn't from there it is possible the cycle was knocked back a bit, or (I'm assuming you have pants) a plant is rotting, or perhaps you are overfeeding

 

Well if it isn't from there it is possible the cycle was knocked back a bit, or (I'm assuming you have pants) a plant is rotting, or perhaps you are overfeeding

My plants all looked green so I don't think it's rotting. Guess I'll wait till tomorrow and test everything.

 

Quoting myself from another post:

Fumasoli, Morgenroth and Udert (2015) indicate that while ammonia- and nitrite-oxidising bacteria are widely observed to have decreasing metabolism in acidic environments, they report that the reasons for this phenomenon are not well understood.

Suzuki, Dular and Kwok (1974) reported that the protonation of ammonia into ammonium ions at low pH is the primary reason for reduced activity, as ammonium is unable to diffuse across cellular membranes for metabolism by ammonia-oxidising bacteria.

However, Wett and Rauch (2003) finds that the low concentration of ammonia at low pH is overstated, and that it is more likely the formation of H2CO3 in acidic media and its volatisation as CO2 reduces the availability of total inorganic carbon necessary for ammonia oxidation. In addition, Gieseke, Tarre, Green and de Beer (2006) suggest that ammonia oxidising bacteria possess ammonium transporters that nevertheless enables the metabolisation of ammonium ions even in acidic environments.

Generally, the lower the pH, the less efficient nitrifying bacteria are at oxidising ammonia or nitrite and a pH of 6.0 is the approximate threshold under which nitrifying bacteria become deactivated (this is different from death). It's important to note that the precise mechanism(s) of action through low pH inhibits nitrifying bacteria is generally unclear.

Most planted tanks which inject CO2 have no issue with partially inhibited nitrifying bacteria. This is likely due to a combination of lower bioloads and high plant density (plants take up ammonium directly and remove the load on the nitrification process). Using a filter media like Seachem Purigen also helps, as it removes excess nitrogenous waste (uneaten fish food, fish waste) and prevents heterotrophic bacteria from processing it to ammonia.

In short: add more plants, feed less, larger and more regular (50% weekly) water changes, more aggressive substrate vacuuming.

 

Co2 and drift wood help lower the ph of any liquidize substance and that is why the amazon has a much lower pH than the rest of the world, it is because of all of the driftwood and Co2 in the water that lowers the pH so much.

 

It’s normal for CO2 to lower ph. Make sure to turn it off at night as it will lower your ph a lot and there will be an oxygenation problem.

I’m not sure why you’re seeing ammonia. Maybe your tank wasn’t 100% cycled. The change in ph could have very well stalled the bacteria’s nitrification a bit. It shouldn’t be a problem though as it will catch up soon. Just keep the ammonia detoxed with Prime.