pH rising in my planted tank - HELP!

[MXFour]

Hello everyone, pioneer of this forum


So i have some problems with pH in my aquarium.. The tank is 200l, i use ADA amazonia soil substrate, there is a big driftwood(which i thought should lower the pH) plus there are some rocks, but i am not sure what those are(not limestone for sure).

dKH of my tank is 4.1, nitrates is around 25, i also use RO water mixed with some tap sometimes. Now when i write this post i'm thinking maybe it is because of dKH, though i think it is pretty normal.
My pH sits stable around 7.77, i used to use co2, but i stopped, because i think i am wasting it with such drastical changes(i want to have pH around 6.4-6.6 stable)..


I can add a photo of my tank if anyone is interested

 

[JackBinimbul]

Might be helpful to show a pic of your tank. Do you have plants? I assume so as co2 would be a waste otherwise! Do you top off your tank? How often do you water change and how much?

 

[MXFour]

Might be helpful to show a pic of your tank. Do you have plants? I assume so as co2 would be a waste otherwise! Do you top off your tank? How often do you water change and how much?

Photo of my tank - https://gyazo.com/3f2882dd7651b23f8a830df837bfa462


Exept that the coral sand you see is removed now, but everything else is as you see. I do 20-30% water change weekly.

 

[King Fisher]

Might have to keep dosing with co2 to lower the pH. Your pH could have risen because you stopped dosing co2???

How much RO are you using? You might have to use more.

 

[MXFour]

Might have to keep dosing with co2 to lower the pH. Your pH could have risen because you stopped dosing co2???

How much RO are you using? You might have to use more.

No, the problem is not that it got high, the problem is that it keeps rising at a fast pace, i'm not sure if i want to put so much co2, that's why i stopped dosing it with co2.


Usually i put 75% of RO and rest tap water, but i thought lower kH = higher pH(not stable pH)?

 

[ZxC]

You are using ADA Aquasoil, which means your pH should be fairly stable in the 6.4-6.6 range.

ADA Aquasoil tanks "must" be run at 0 dkH because the soil buffers out carbonates.

You are adding carbonates by using tap water and therefor exhausting the Aquasoil of it's buffering ability.

It's likely ad / ab sorbed all the carbonates it can, which is why your pH is higher now.

I wouldn't stop using CO2. You can easily have the pH into the mid 5's when using CO2 and Aquasoil without issue.

 

[Funken_A]

If you are unsure of the rocks I would think about those as well.. Place them in a bucket and monitor the PH outside of your tank. if they raise the PH in the bucket then you have your smoking gun

 

[MXFour]

You are using ADA Aquasoil, which means your pH should be fairly stable in the 6.4-6.6 range.

ADA Aquasoil tanks "must" be run at 0 dkH because the soil buffers out carbonates.

You are adding carbonates by using tap water and therefor exhausting the Aquasoil of it's buffering ability.

It's likely ad / ab sorbed all the carbonates it can, which is why your pH is higher now.

I wouldn't stop using CO2. You can easily have the pH into the mid 5's when using CO2 and Aquasoil without issue.

It rises 0.01 in 1-1:30 minutes. Is this ok? I would like to have more stable pH though, what would you advise me to do for stability?

 

[ZxC]

It rises 0.01 in 1-1:30 minutes. Is this ok? I would like to have more stable pH though, what would you advise me to do for stability?

Either start over with fresh ADA and use gH only boosted 100% RO or use your current setup with 100% tap until the soil has FULLY lost it's buffering ability.

As of now, you are not on the right track for a stable pH. The tap water carbonates are at war with the ADA soil.

Or, just start over with inert substrate and use your 75/25 mix.

 

[MXFour]

Well i am thinking of moving to a new apartment, then i will make a fresh start, as for now, i will keep doing what i do.


Thanks for the answers!