PH high in planted ten gal

[katienewbettakeeper]

it’s kind of embarrassing how much i post on here but I always seem to run into problems lol. Just did a ph test two days after a 30% water change, and my ph was super high in my ten gallon. like around 9.0. Immediately did a 50% water change, and now it’s back around 7.5. my tap water is 7.0 so it can’t be high from that. My betta fish is doing fine, no signs of illness. I think it’s possible that because i have sooooo many plants they might have been sucking up all the carbon dioxide and in turn making my ph super high? or could it be something else? How can I keep this from happening again? I have a lot of almond leaves in my tank, but they clearly aren’t lowering ph? I took out a handful of floaters but there’s still a lot, and i love them so i don’t want to get rid of them. how can i combat this?

 

[Rocky998]

What decor do you have in the tank and what's the substrate made of? The plants would not have sucked up enough CO2 to turn your water from 7.0 to 9... It just seems really weird

 

[StevenF]

The only time I saw PH that high was due to my lights and plants. I found in my tank that when the lights are on the PH goes up.The peak PH occurred right before the lights turn off. Once the lights ar are off the PH drops. So I would take to PH measurements one just before the lights turn on and one just before the lights turn off.. I was able to reduce this by dimming my lights.

I believe that plantsman consume carbonates. So if you have Calcium carbonate in the water the plants would consume he carbonate leaving the calcium in the water. The calcium then converts to calcium hydroxide (which pushes the PH up)and then overnight reacts with CO2 from the air or fish to convert back to Calcium carbonate. If so you might find your PH at 7 just before the lights turn on.

 

[Colin_T]

I doubt there's enough plants in the tank to cause the pH to go up to 9.0 through photosynthesis, especially if there is some surface turbulence. You also have a couple of low light plants that are slow growers when kept underwater and these won't be doing much to produce oxygen ad remove the CO2 from the water.

I would monitor the tap water over the next few weeks and test the gravel and rocks in the tank.

Get a couple of handfuls of gravel and put them in a bucket of distilled water. Monitor the pH of that bucket of water over the next week and see if the pH changes. Do the same with the rocks. Have a separate bucket of water that has nothing in and monitor the pH of that too.

If the plants are actually causing the pH to go up during the day, either reduce the light intensity or increase aeration/ surface turbulence to help balance the dissolved gasses in the water.

 

[katienewbettakeeper]

What decor do you have in the tank and what's the substrate made of? The plants would not have sucked up enough CO2 to turn your water from 7.0 to 9... It just seems really weird

two pieces of driftwood, and my substrate is fluval stratum and fluorite red. I have a standing thermometer as well. I really have no idea what else could have caused it

 

[katienewbettakeeper]

The only time I saw PH that high was due to my lights and plants. I found in my tank that when the lights are on the PH goes up.The peak PH occurred right before the lights turn off. Once the lights ar are off the PH drops. So I would take to PH measurements one just before the lights turn on and one just before the lights turn off.. I was able to reduce this by dimming my lights.

I believe that plantsman consume carbonates. So if you have Calcium carbonate in the water the plants would consume he carbonate leaving the calcium in the water. The calcium then converts to calcium hydroxide (which pushes the PH up)and then overnight reacts with CO2 from the air or fish to convert back to Calcium carbonate. If so you might find your PH at 7 just before the lights turn on.

I did have my lights on pretty high, but last week I also did a two day blackout on my tank to get rid of some green algae that was killing my floaters. looking back I definitely should have checked PH when I saw the algae, oops.

 

[Rocky998]

Dang I was really hoping you had some weird mineral rock in there lol... I seriously dont know whats wrong but that PH is VERY high

two pieces of driftwood, and my substrate is fluval stratum and fluorite red. I have a standing thermometer as well. I really have no idea what else could have caused it

 

[katienewbettakeeper]

Dang I was really hoping you had some weird mineral rock in there lol... I seriously dont know whats wrong but that PH is VERY high

yeah it’s freaking me out. I’m gonna monitor it and my tap for the next week, and do water changes if it gets above 8 again. I might see if I can save up and buy a new testing kit, as well as a GH and KH kit, the one I have now is the topfin freshwater master kit and I’m not sure if it’s accurate. I’ll do some investigating over the weekend to see if i can find any cause, but for now it’s just a mystery. i feel like the universe doesn’t want me to have an aquarium

 

[katienewbettakeeper]

I doubt there's enough plants in the tank to cause the pH to go up to 9.0 through photosynthesis, especially if there is some surface turbulence. You also have a couple of low light plants that are slow growers when kept underwater and these won't be doing much to produce oxygen ad remove the CO2 from the water.

I would monitor the tap water over the next few weeks and test the gravel and rocks in the tank.

Get a couple of handfuls of gravel and put them in a bucket of distilled water. Monitor the pH of that bucket of water over the next week and see if the pH changes. Do the same with the rocks. Have a separate bucket of water that has nothing in and monitor the pH of that too.

If the plants are actually causing the pH to go up during the day, either reduce the light intensity or increase aeration/ surface turbulence to help balance the dissolved gasses in the water.

I’ll monitor the tap for sure, i’m skeptical that it’s my substrate because it’s just flourite red and fluval stratum, and neither of those should raise ph ? Also, I don’t have any rocks in my aquarium, just driftwood.

 

[Byron]

I concur with most if not all of posts 3 and 4 here. A pH shift is common in planted tanks...one reason why you should always test the pH at the same time of day in any tank. But aside from that, this is quite a large change, and it may well be due to other factors in addition to the normal planted issue. Fluval stratum is one possible factor, along with the rock. Colin dealt with these.