Using Peat To Lower Water pH

[jaypeecee]

Hi Folks,

In one of my tanks, I need to lower the water pH to around 6.5, i.e. slightly acidic. The current pH of this tank is 7.54 and alkalinity/carbonate hardness is 3.0 dKH. I'm wondering about using peat, something I've never done before. Can anyone suggest a suitable product? I would need to add the peat to a small internal filter. The tank is only 15 litres. CO2 injection is not currently used on this tank. To what extent does the peat colour the water? I realize that it's difficult to quantify this but any guidance is better than nothing. Anything else I should know?

Thanks in advance.

JPC

 

[timdjones10]

Why do you want to lower the PH? Peat is a pretty old fashioned method as it's unsustainable to harvest, something like this better

 

[jaypeecee]

Why do you want to lower the PH? Peat is a pretty old fashioned method as it's unsustainable to harvest, something like this better

Hi @timdjones10

The first reason is because I have been advised that it would benefit my plants if the water is somewhat acidic. And this has come from a reliable source. More details to follow. The second reason is because it has been scientifically demonstrated that cyanobacteria (aka BGA) prefer alkaline environments. Having had a few problems with cyano, I thought I'd put the scientific research to the test.

I realized a little while after starting this thread that here I was suggesting the use of a precious natural resource. So, let's scrap the idea of using peat and use something else - natural or chemical.

All suggestions welcome.

JPC

 

[jaypeecee]

Hi @timdjones10

There is no way that I'm going to use muriatic acid, which I understand to be hydrochloric acid. I don't think it's necessary to use such a strong acid. I'd rather use a weaker acid and reduce KH. But, it needs to be stable. In the first instance, I'm going to see if I can achieve my objective simply by injecting CO2.

JPC

 

[Wookii]

Adding botanicals will reduce your KH John, such as alder cones, catappa leaves and bark etc. The tannic, fluvic and humid acids they release, along with a number of other compounds are beneficial to plants, fish and shrimp alike.

If you don’t want them visible in the tank (though I think they look great on the substrate), they can be added to the filter instead.

They will stain the water to varying extents. I quite like a bit of colour to the water, but if you want to avoid that, you can use pre-prepared extract products.

Several of these options are discussed in this thread:

Thoughts on Blackwater Extract products . . .

Does anyone have experience or thoughts on blackwater extract products such as: Easy Life Catappa-X Tetra Blackwater Extract /Touramin Aquadip Liquid Catappa Dennerle Humin Elixir Salty Shrimp Leaves and Bark (extract) GlasGarten Humin+ I do add botanicals (catappa leaves, catappa bark, alder...

www.ukaps.org

 

[sparkyweasel]

A weaker acid sounds more suitable, especially an organic acid such as might occur in the natural habitat of your plants and livestock, - humic acid springs to mind.
Peat is a contentious issue in horticulture, some producers claim that their product is sustainable and ethical, eg;
Evergreen Peat

 

[jaypeecee]

Adding botanicals will reduce your KH John, such as alder cones, catappa leaves and bark etc.

Hi @Wookii

I experimented with botanicals some time ago but found they made minimal difference to KH and/or pH. Specifically, I tried Catappa leaves and Oak leaves. Then, I read this article in PFK, which supported my findings (please scroll to the end of the article for the interesting figures):

Using leaves in your tank

Collect fallen leaves from a nearby forest and use these to decorate your tank.

www.practicalfishkeeping.co.uk

JPC

 

[jaypeecee]

A weaker acid sounds more suitable, especially an organic acid such as might occur in the natural habitat of your plants and livestock, - humic acid springs to mind.
Peat is a contentious issue in horticulture, some producers claim that their product is sustainable and ethical, eg;
Evergreen Peat

Hi @sparkyweasel

Many thanks for the feedback. I'll check out your suggestions.

JPC

 

[John q]

In the above linked article it suggests catappa leaves would drastically reduce the ph in ro water and lower it a bit in tap water. Wouldn't a mix of the two give you the desired result jpc? Or doesn't in work like that.
Anyway interesting article non the less as I'm experimenting with catappa to try and tint the water slightly.

 

[Wookii]

Hi @Wookii

I experimented with botanicals some time ago but found they made minimal difference to KH and/or pH. Specifically, I tried Catappa leaves and Oak leaves. Then, I read this article in PFK, which supported my findings (please scroll to the end of the article for the interesting figures):

Using leaves in your tank

Collect fallen leaves from a nearby forest and use these to decorate your tank.

www.practicalfishkeeping.co.uk

JPC

It depends how many you add and your starting KH. Your KH is already pretty low, so it should take much to lower it further and a decent pH drop to be seen. A few alder cones should do it.

As for the tabulated data in that article, we don’t know the starting KH of the tap water - it must be fairly high as it has a degassed pH if 8.0, but even so the data shows a substantial reduction in the pH from the addition of the Catappa leaves. At 311 hours there is a 1.1 pH reduction in the sample with the Catappa leaves versus the untreated sample.

 

[jaypeecee]

As for the tabulated data in that article, we don’t know the starting KH of the tap water - it must be fairly high as it has a degassed pH if 8.0, but even so the data shows a substantial reduction in the pH from the addition of the Catappa leaves. At 311 hours there is a 1.1 pH reduction in the sample with the Catappa leaves versus the untreated sample.

Hi @Wookii

Yes, you are correct about the 1.1 pH reduction. Why would the pH of the reference hardwater increase over time? You might expect it to absorb CO2 from the surrounding air but that would take the pH down. I seem to recall that I did a few measurements myself with Catappa leaves but it would be easier for me to do another set of experiments rather than try to find the previous set. For more information about humics, I suggest you try searching for Christian Steinberg who is the authority on this topic.

OK, so returning to the matter in hand, I will re-consider the use of humics for lowering pH. I don't mind a slight yellowing of the water but I wouldn't want it stained brown for my main tank.

Thanks for the dialogue - this has been useful.

JPC

 

[Wookii]

Hi @Wookii

Yes, you are correct about the 1.1 pH reduction. Why would the pH of the reference hardwater increase over time? You might expect it to absorb CO2 from the surrounding air but that would take the pH down. I seem to recall that I did a few measurements myself with Catappa leaves but it would be easier for me to do another set of experiments rather than try to find the previous set. For more information about humics, I suggest you try searching for Christian Steinberg who is the authority on this topic.

OK, so returning to the matter in hand, I will re-consider the use of humics for lowering pH. I don't mind a slight yellowing of the water but I wouldn't want it stained brown for my main tank.

Thanks for the dialogue - this has been useful.

JPC

As mentioned in that thread I linked to, you can buy premade liquid extracts such as Easy Life Catappa X, or the Mircobe Lift product that @X3NiTH uses, that contain the acids etc without so much tannins, so minimal, if any, water discolouration, and can be dosed in a more controlled manner I that’s something you prefer to do.

 

[Conort2]

Any chance you could use rainwater or Ro water and mix it with your tap?

 

[jaypeecee]

Hi @Wookii

I keep forgetting your first name - is it Gareth? I apologize. This sure is a sign of age!

You may be onto something. I've always associated humic and fulvic acids with tannins and, therefore, brown colouration. I'll definitely check out the Easy-Life and Microbe Lift products.

Thanks again, my friend.

JPC

 

[jaypeecee]

Any chance you could use rainwater or Ro water and mix it with your tap?

Hi @Conort2

I'm not sure why that would result in slightly acidic water. My objective is to have tank water with pH from 6.0 to 7.0. Obviously KH and GH are also important considerations.

JPC

 

[MichaelJ]

I've been using Fluval Peat Granules way in the past mostly for the plant enrichment effect (which I didn't really appreciate and why I stopped using it). Over time It didn't do much with Ph either (and I used quite a bit). The browning effect (from tannins) was minimal, probably in part due to my filtration over Seachem Purigen and having it leach out in a bucket of water for a couple of days before putting it on the filter.
Cheers,
Michael

 

[Wookii]

I've been using Fluval Peat Granules way in the past mostly for the plant enrichment effect (which I didn't really appreciate and why I stopped using it). Over time It didn't do much with Ph either (and I used quite a bit). The browning effect (from tannins) was minimal, probably in part due to my filtration over Seachem Purigen and having it leach out in a bucket of water for a couple of days before putting it on the filter.
Cheers,
Michael

Purigen will absorb the organic acids from the peat along with the tannins - you were giving with one hand, and taking away with the other. Also lot of those beneficial acids and other compounds would have been left behind in your bucket unfortunately.

 

[sparkyweasel]

Why would the pH of the reference hardwater increase over time?

Unfortunately we only have the tables and no information about the experiment.
It's possible that he measured the pH of freshly-drawn tapwater which then warmed to room temp in the course of the experiment, causing offgassing of CO2.
We also aren't told how many leaves in how much water resulted in those changes.

 

[Conort2]

Hi @Conort2

I'm not sure why that would result in slightly acidic water. My objective is to have tank water with pH from 6.0 to 7.0. Obviously KH and GH are also important considerations.

JPC

More for the reduction in KH and GH. I wouldn’t have thought Adding botanicals will make much difference unless you have water with a low tds to start with, however I could be wrong.

 

[jaypeecee]

Hi Folks,

If other aquarists are unaware of the following, it seems appropriate to mention it here:

Is pH important in a planted aquarium ?

What is pH? Does it matter in a planted aquarium and what range is a good target if so ? This page explains what pH reading means to your planted tank setup.

www.2hraquarist.com

There is a wealth of useful information on the above linked page.

JPC