low pH?

[Cor]

Hi all,

two and a half question:
- what pH values do you get when using an aquasoil. Or asked differently: how far does the pH drop with the use of aquasoil
- and if you use CO2, will the pH drop even further?

cheers, Cor

 

[Cor]

found a pic

I see in the list that the pH in the soil drops to pH 5.73. So I make a connection here with 'melting' of plants in the start-up phase.
The soil is simply too acidic, and the low pH makes it difficult to absorb nutrients. Thus over time the melting will decrease as the pH will reach acceptable levels 🤔

 

[dw1305]

Hi all,

I see in the list that the pH in the soil drops to pH 5.73. So I make a connection here with 'melting' of plants in the start-up phase.

I don't know the answer, and "too acidic" may be that answer, but I'm not sure the <"pH is that relevant">.

The reason is that the tap water only <"had 2 dKH carbonate hardness"> and that is <"less alkaline"> than the rainwater I use. I'm going to guess if you had started with <"our tap water"> (for example) you wouldn't have got any pH effect at all.

So I make a connection here with 'melting' of plants in the start-up phase.
The soil is simply too acidic, and the low pH makes it difficult to absorb nutrients. Thus over time the melting will decrease as the pH will reach acceptable levels

It is going to depend on the plant, but generally nutrients are easy to uptake in acidic water. My guess is the melting relates to the <"Total Ammoniacal Nitrogen (TAN) content"> - <"My unfortunate vacation experience and "who dun it"">.

found a pic

I'll be honest I don't understand why ADA add that much TAN to their substrate, my entire aim is to remove any ammonia as quickly as possible, and I <"can't see any advantage"> to that level of ammonia addition.

Cheers Darrel

 

[Cor]

I don't know the answer, and "too acidic" may be that answer, but I'm not sure the <"pH is that relevant">.

I make this conclusion through this overview.

 

[John q]

I make this conclusion through this overview.

I wouldn't make to many concrete conclusions from the Soil pH ~ Nutrient uptake charts.
Firstly they are designed for terrestrial plants grown in soil, not aquatic plants grown under water.
Secondly, even if we assume aquatic plants respond in a similar manner to their land based cousins the nutrient uptake doesn't suddenly stop at a given ph, it merely "Reduces".

Here we can see that at a ph of 5.5 availability is there for all nutrients, just diminished in some.

With co2 i drop my ph to 5.7 and whilst I may have issues I doubt low ph is the culprit, others go much lower than this.

@_Maq_ is running various tests and currently a ph of 5.4 without co2 injection, the plants appear to be doing fine.

His journal is worth a read regarding low ph worries and plants.

Maq's Substrate Experiment

I'm considering a new experiment, and there are some points I'd like to get your advice about. I want to check behaviour of a "typical" aquasoil compared to sandy substrate, and a sandy substrate with and without "typical" root tabs. Some of you already know my experimental workstation. I...

www.ukaps.org

 

[aquanoobie]

Hi
The soil will buffer it's pH. You can't change it much and that's good, let it be. Plant roots will create their own micro zones and take the nutrients they need.