Ph difference: how much is too much?

[Hallyx]

Sourcewater Ph 7.4+- @ 0 hours 7.8+- @ 24 hours 8.0+ @ 48 hours Tankwater Ph 7.4+- @ 0 hours 7.6+- @ 24 hours 7.6+ @ 48 hours How much difference in Ph can Betta tolerate (as with a 100% water change) without having to acclimate? Thank you, Hallyx

[Hallyx]

Sorry about the mess. I'm tired of and quite discouraged by trying to get this system to format correctly. Simple paragraphs and tables seem to be beyond my abilities here. Can anyone wade through that and answer my question: How much PH difference can these fish tolerate without undue stress? Thanks, Hallyx

[Oldfishlady]

Its normal for the source water pH to change once it has degased...usually it decrease slightly.....as long as you do proper acclimation with the 100% water changes it shouldn't be problematic.....Bettas are pretty tough and tolerate a lot...but you still don't want to shock them too much since it stresses them and can compromise the immune response...

Its odd how your source water increase.....is this source water in a clean glass...not the tank with a 24h degas using a reagent type test kit...not strips.....

[Hallyx]

Its odd how your source water increase.....is this source water in a clean glass...not the tank with a 24h degas using a reagent type test kit...not strips.....[/quote]

Thank you, Ma'am I too thought it was odd to have the degassed Ph go up. This was in a clean one-gallon plastic container. As I expected, the tank Ph went up more slowly. I guess the ammonia (acidic) kept the tank water less alkaline compared to the control container. I'm using an API master test kit. I check ammonia every other day and do an 80% change when ammonia reaches .25ppm, both in my divided 4 gallon and in my 2 gallon. About every 3 days on average. Are you suggesting I remove my fish at every change and reaclimate them? I'm sure they won't like that; I know I don't. Removing the fish is more stressful for me than them, I think.

[Oldfishlady]

I would only remove the Betta if you did a 100% water change...not needed with partial changes.....

Try testing the source water in a clean glass container-plastic can sometimes leach and/or absorb things- that could cause skewed results......you also need the water to be able to gas out and the larger the surface area the better for gas exchange or even adding an airstone

Pour a clean wide mouth glass of water-test- then wait 24h-test- and compare number-test tank and compare number...this can tell you CO2 content and if anything in the tank is causing changes..

[Hallyx]

Thanks again, Ma'am, for your advice in this matter.

I repeated this experiment using my sterilized QT tank as the control. Here are the results:

Sourcewater
0 hrs 7.6 pH
24 hrs 8.0 pH
48hrs >8.0 pH

Tank
0 hrs 7.6 pH
24hrs >7.6 pH
48hrs >7.6 pH

This has really got me baffled. If I have CO2 in my well, the outgassing should increase the pH. But the ammonia buildup from the fish should increase the pH even more, however slightly (I misspoke in my last post).

By the way, the creek that runs by the house has a pH of 7.6, the same as my well water. That has me scratching my head.

None of this is critical, I know, and the fish are delighted with their water changes; even playing in the water that I'm pouring into the tank.

I just want to know what is considered a safe pH difference that will not shock the fish.

Thank you, once again, for your time and expertise,

Hallyx

[bahamut285]

Originally Posted by Oldfishlady

Its normal for the source water pH to change once it has degased...usually it decrease slightly

When you remove gas from a water source (usually CO2) it INCREASES the pH, not decrease.

@Hallyx: In your chart, what is the difference between Source and "tank"? Is the tank just a box of treated water? Or is it in your tank with fish?

Generally the second it comes up from the well, it is very concentrated with CO2 gas, and takes a while (as seen on your chart) to completely dissipate. Ammonia build up generally does not directly affect the pH unless you have a lot of plants to denitrify the ammonia/ammonium.

This also depends on the alkalinity of your water, if your alkalinity is high, then changes will not be significant.

In terms of the health of your fish, 7.6-8.0 over the course of 24h is fine. A sudden (almost immediate) change of 7.6-8.0 MAY be a concern (to more sensitive species), but as long as your fish are not acting depressed/shocked then it is generally not a major concern.

[Hallyx]

@Hallyx: In your chart, what is the difference between Source and "tank"? Is the tank just a box of treated water? Or is it in your tank with fish?<p>
<p>
Sourcewater is untreated tapwater at 78*F. Tank is 4gal untreated tapwater with two Betta. <p>
<p>
Ammonia build up generally does not directly affect the pH unless you have a lot of plants to denitrify the ammonia/ammonium.<p>
<p>
I am a little surprised that .25ppm ammonia doesn't seem to affect pH measurably. I wonder how much it takes.<p>
<p>
This also depends on the alkalinity of your water, if your alkalinity is high, then changes will not be significant.<p>
<p>
Even though alkalinity (and, conversely, acidity) increases on a logarithmic scale?

Thank you for furthering this discussion, Bahamut. I know you wrote the tutorial on water most frequently referenced here. I'm interested in finding out more about hardness, too, as I'm considering the possiblity of keeping wild-type Betta sometime in the far future.

[bahamut285]

Sourcewater is untreated tapwater at 78*F. Tank is 4gal untreated tapwater with two Betta

This is not a sound experiment because there are too many variables. However, from what I can see it is the fish that are exchanging carbon dioxide into the water, causing it to stay fairly low. There may also be other things in your tank causing this.

I am a little surprised that .25ppm ammonia doesn't seem to affect pH measurably.


Why? It doesn't. pH would only affect the toxicity of ammonia. Ammonia doesn't affect pH unless it is being denitrified in a manner that adds a ridiculous amount of H+ to the water.

**EDIT: Okay it DOES affect pH, but you would need a ridiculous amount of it to do so. Definitely way more than you are measuring that would kill your fish.

Even though alkalinity (and, conversely, acidity) increases on a logarithmic scale?

Alkalinity. You are confusing it with basicity. Alkalinity is the ability of a solution to neutralize and resist pH changes. Low alkalinity means your pH will be the same way as you perform acid/base neutralization. For example pH 6 solution thrown into a pH 8 solution will come out exactly as 7, essentially an unstable pH which can cause shock to your fish. A high alkalinity solution means i will probably not affect it as much, maybe bringing the pH 8 solution down to maybe 7.6 instead of all the way to 7, this is more stable and favourable to fish keeping. Low alkalinity is not healthy for fish.

As for hardness, it is somewhat related to alkalinity but I suggest further reading on your part, as it is difficult to properly explain. It can be fairly easily increased and decreased with proper equipment or dosing tablets.