Alkalinity, buffering & Hardness?

[Sonia]

Hi!

On Monday I stopped using my air pump because I felt that my plants would provide enough oxygen for my fish - so far they all seem fine. (Re: "Enough Oxygen?" - Nov. 30). However my PH & Alkalinity have gone down as a result:

-PH from around 6.7 to 6.3
-Alkalinity from around 60-80 to almost 0

My tap water PH is about 6.5 and is very soft (like my tank water - about 40ppm - 2dH), so I have chosen to keep fish that need slightly acid water (see my signature). These water conditions are therefore ok (for now), but I'm worried about a couple things:

Because my alkalinity and hardness are so low, does this mean that my water will be susceptible to quick PH changes (since it has a very low buffering capacity)? I read this is bad, but I'm not sure....

Is there anything I can do to maintain the PH without having to use any chemicals (which I hear is bad)? Is low Alkalinity not that bad and I'll be fine? I'm not sure how much/quick of a PH change is bad for my fish....

FYI I have a few pieces of driftwood as well as peat filtering in my tank. My tank has been started for 2 months and I've been doing weekly 10% water changes for the past month (and will continue to do so).

I feel like going with an acid aquarium may be a little touchier than going with an alkaline one... I'd just like to get as many tips as possible to avoid possible disasters... thank you very much!!!

 

[BrianNY]

Hi Sonia. You're correct on this. If you don't buffer the tank your pH will continue to fall. This is a topic that's gotten alot of questions on AA. There's a thread in the Freshwater Getting Started section started by gfink titled "need help establishing a buffer". Please read that thread all the way through as it contains the answer and solution for your problem.

 

[Sonia]

Perfect! Thanks, I'll check it out...

 

[Sonia]

I read the "need help establishing a buffer" thread....
I am thinking I'll try adding the crushed coral in the filter, though that will increase my PH slightly. I hope that this increase won't be too bad or too fast for my fish.

The general consensus at AA seems to be that it is better to have a stable PH than to have an ideal (if ideal for your fish is acidic), low and unstable PH? And there is no way to stabilise your PH (without chemicals) AND keep it low? I guess I'm somewhat dissapointed that there isn't, but I'm also happy that the actual value of my PH isn't that important. Let me know if there's anything else I should know! Thanks!

 

[malkore]

What's odd though, is that stopping the use of an airstone should in no was affect alkalinity. What brand of test kit are you using for alkalinity?

And it definitely is better to maintain a stable pH than an ideal pH for about 90% of freshwater fish species (discus and cichlids are another story).