PH Increase-Should I be freaked out?

[chichian]

Okay, so I think my tanks been running for about 3 months now. I have tested my PH on a total of 4 occassions now (including tonight's reading). During the first 2 months is when I tested 3x. I always got ~6.5PH (Aquarium Pharm liquid tests). I was actually kinda worried that it would drop too low, so I never got any real driftwood for my pleco, but at the same time, although I never tested for hardness, I knew that Vegas had REALLY HARD water, so I wasn't that worried about PH fluctuations.

Now, tonight, a little less than month later after my last PH test (6/17), I get a result off the charts from the HIGH RANGE PH TEST... indicating >8.8. I assume it's off the charts since it was like a light almost hot pink and the 8.8 is a darker pink. 8.4 is brownish-pink-purple. 8.2 is brown. Okay, so, albeit by means of inprecise test strip (Jungle Labs), I tested my KH & GH for the first time and I get ~180ppm KH (labeled as "ideal" on the bottle), and a GH of ~300ppm (labeled as "Very Hard"--I knew this about Vegas h20--this is the LAST color though, so it could be higher I'm guessing). These results are no surprise really on they're own but I thought that KH buffered against PH swings, so in a little less than a month, my PH has gotten INSANE!!

What's up with this? I had tested first (2x in fact to make sure it wasn't bunk) w/ the low range PH kit since I was assuming it would be about the same as last time, but it was the highest color (7.6). I then tested the tap water with the low range test, and it was about 7.0PH (sounds about right). Then that's when I used the high range.

OK, so now for my stupid question: What causes PH to rise and could cause this much of a jump? I know something basic has to be introduced into the system right? Maybe left over solids from evaporation accumilating (I don't know I'm taking stabs at anything here)???... is rising PH normal when you have such hard water??? I don't know and it's been years since my last chem class .

Any ideas/insights/knowledge happily accepted.

Should I be worried?. I am kinda worried since it seems so drastic, but the fish seem very happy and healthy.

Oh yeah, the substrate is Schultz's Aquatic Plant soil and isn't supposed to alter PH. I have two fake driftwood like thingies in there (from PetSmart), plants, and fish.

 

[Lotus]

You should probably do a control test of your tapwater, but leave it to sit out in a glass for 24 hours before you test it.

Did you test with a low-range pH kit as well? It's possible you're getting a false reading from the high-range kit, or misinterpreting the color reading.

Any idea why your pH was at 6.5 before? That seems low for Vegas.

 

[chichian]

Thanks Lotus.

Any idea why your pH was at 6.5 before? That seems low for Vegas.

I don't know why it was 6.5 like that before. I'm fairly certain that is probably close to correct readings from back then though (at least it was consistent).

The first test I ever did on the tank, I tested with the High Range test first since I was assuming that Vegas had high PH water since it had hard water. But it registered the lowest color. So then I tested twice with the Low Range and got 6.5. The other subsequent tests during the first two months of the tank life, I just used the Low Range test, since I didn't think it would shift that much. They came out 6.5 too. So this was consistent readings at least.

I should have tested the tap water back then since that could have been what has changed. Or perhaps because I used the hose to fill it up initially? I haven't used the since since it's hard to control the temperature, but then after that I was using the kitchen sink for a while and then started using the bathtub's faucet since it has a much higher flow rate. Can it vary from faucet to faucet even?

Did you test with a low-range pH kit as well? It's possible you're getting a false reading from the high-range kit, or misinterpreting the color reading.

Last night, I tested twice with the Low-Range first because it was the highest color. I couldn't believe it the first time, so I tested again. The results were the same. Then I thought perhaps the test had gone bad (especially since the AC had broken, so perhaps the heat and aided in it's demise), so I tested the tap and that's when it gave me reading of 7.0 for the tap--I thought this was reasonable since I thought most water companies try to deliver close to neutral water. Anyway, I then figured the Low Range was still good and then I tested with the High Range and got that funky pink color, so yeah, I could have totally misinterpretted color or screwed it up. But I think the PH is definitely above the range of the Low Range test.

Tonight I will dilute the tank water and test again w/the High Range test and see if it shows a registerable color and leave some water out to do the control test.

Thanks again!

P.S. What is the shelf life of a test kit anyway (after opening)?

 

[chichian]

Okay, I guess my tap water just varies a lot. I contacted the water company, they said the water varies from 6.5-8.0 PH per federal regulations. I think this maybe why my tank was around ~6.5 before, although with the control test, I don't know why it wouldn't have gone to 7.5 immediately, but oh well.

The other day I retested everything:
(1) My control test: sample started at ~7.0 PH (fresh) , next day it was ~8.0 (aged).

(2) I redid my tank test, and it was around ~8.0. So I guess I misinterpretted or screwed up the high range from before.

(3) I tested some fresh tap again, and it was ~7.2 this time.

I guess from this, I'm thinking, I should NEVER do a water change > 25% since the difference would be so great and then the next day difference is a full increment. Or I need to leave the water out ahead of time.

Thanks again Lotus!

 

[GoldLenny]

I'm in New Orleans (the other Sin City...) and we have hard water too. I use the AP Master Test Kit and my water used to be around 7.5 pH but lately, it has risen to the 8.0 range. I've also noticed that the temperature out of the tap has gone from the low 70's during the winter to the low 80's now. I'm not positive but I bet the warmer water is causing the calcium and scale buildup in the municipal and building pipes may be leaching into the warmer water. I'm not a chemist but I know that warmer or hot water will dissolve things that cooler water will not. That's just my educated guess. I've been seeing tons of posts about higher pH in the past month and I'm betting it has to do with the warmer water in the pipes.

 

[twoluvcats]

has vegas been getting rain? Here, our pH swings when our water system is innundated with rainwater.

 

[chichian]

Recently it's rained, but I haven't tested the PH lately. I don't remember when it was around 6.5 if we were getting a lot of rain or not. I think I'm just accepting the fact that it varies and thus, now I know just to never change out too much water at once. I'm currently soaking some driftwood though to add to the tank . I guess knowing my KH now, I feel safer adding it.

Yeah , it might be temperature related as you've said GoldLenny. That would make sense as the temperature here keeps rising... haha and my ac just broke again today.
Ah... the sun gods must hate me and want my fish and cats to be hot too. Actually I should do a test and see if it's closer to 8 fresh out of the tap (since it's so hot).