Tank water pH higher than tap water

Tested all 3 of my tanks today, and the pH is reading quite high (as expected, hard well water). I decided to test my water straight out of the tap since I was curious, but for some reason it’s reading way lower than the tank pH. Which is odd. I don’t have anything in the tanks that would cause the pH to rise. If anything, it should lower a bit, since I have catappa leaves as well as small pieces of driftwood. Not sure what’s going on here. Pic attached. Clearly the 3 tanks are all very similar pH, but the one on the far left (tap) is different.
Tanks readings: 8.2-8.4
Tap reading: 7.8? It’s hard to tell.
Fish are all doing fine, despite keeping species that prefer slightly acidic water.

 

some people have tap ph that changes seasonally but do you have any rocks in those tanks? pagoda stone for example will raise your ph a bit

 

some people have tap ph that changes seasonally but do you have any rocks in those tanks? pagoda stone for example will raise your ph a bit

Nope. Sand substrates, a couple of decorations, catappa leaves, little chunks of driftwood. A few live plants. Not sure what is causing the difference. I just did water changes on all tanks within the last 2 days and it’s already reading this high compared to the tap. One tank does have sand that I took from a nearby lake, which probably contains limestone and whatnot. The reading wasn’t that much different compared to the other tanks though. They were all roughly the same.
Sand in other tanks is store bought pH neutral aquarium sand.

 

Completely normal. Most people test pH straight out of the tap, which is ill-practice. CO2 often builds up in tapwater, and will degas when left out (like being in a tank or a bucket or a glass). As the CO2 off-gasses, the pH will gradually rise until the true pH value it met.

Let your tapwater sit out for 24 hours in a glass, and then test pH. It is likely higher - and closer to your tank's value.

 

Completely normal. Most people test pH straight out of the tap, which is ill-practice. CO2 often builds up in tapwater, and will degas when left out (like being in a tank or a bucket or a glass). As the CO2 off-gasses, the pH will gradually rise until the true pH value it met.

Let your tapwater sit out for 24 hours in a glass, and then test pH. It is likely higher - and closer to your tank's value.

Ohhhh this makes much more sense! Thanks for the explanation. I’ll try this.
If my tap water pH is truly this high, I should consider keeping African cichlids lol. My other fish don’t seem bothered though.

 

Ohhhh this makes much more sense! Thanks for the explanation. I’ll try this.
If my tap water pH is truly this high, I should consider keeping African cichlids lol. My other fish don’t seem bothered though.

Africans would like it yes, as would 95% of commonly available aquarium fish. pH doesn't really bug most fish.

That's why KH and GH are more important than pH in my opinion. KH basically determines the pH anyway, and GH measures Ca and Mg which are essential elements.

My fresh tapwater reads 7.6 and degasses to 8.2.

 

Tested all 3 of my tanks today, and the pH is reading quite high (as expected, hard well water). I decided to test my water straight out of the tap since I was curious, but for some reason it’s reading way lower than the tank pH. Which is odd. I don’t have anything in the tanks that would cause the pH to rise. If anything, it should lower a bit, since I have catappa leaves as well as small pieces of driftwood. Not sure what’s going on here. Pic attached. Clearly the 3 tanks are all very similar pH, but the one on the far left (tap) is different.
Tanks readings: 8.2-8.4
Tap reading: 7.8? It’s hard to tell.
Fish are all doing fine, despite keeping species that prefer slightly acidic water.

I had this same problem, what you need to do is take some of your tap water, let it sit for 24 hours, then test it. And that worked for me, the ph matched.

 

Africans would like it yes, as would 95% of commonly available aquarium fish. pH doesn't really bug most fish.

That's why KH and GH are more important than pH in my opinion. KH basically determines the pH anyway, and GH measures Ca and Mg which are essential elements.

My fresh tapwater reads 7.6 and degasses to 8.2.

I see. I don’t have a GH/KH test kit, but I do know that my water is very high in minerals. Sometimes the filters have an orange hue to them due to the iron, I also get algae growth because of it. Calcium I for SURE have lots of, since I have to scrape calcium deposits off the glass on all tanks. Usually every water change. Otherwise it builds up too much and becomes hard to see into the aquariums. Heaters also have calcium buildup on them.
I don’t know if this is a problem, but my fish are doing fine. Snails especially. Only downside is having to constantly scrape it.

 

My fresh tapwater reads 7.6 and degasses to 8.2.

Mine is exactly the same.