Barr GH Booster makes water acidic?

If your pH after injecting co2 is 5.5, the degassed pH is probably around 6.5 - 6.7, not too bad. It would be normal for tap water that has near 0 KH (like mine), if you are not adding anything to boost KH or anything that would be leaching KH into the tank to cause it to rise. Another issue that could crop up in low KH tanks is that if you're not removing enough of the waste from the substrate, or doing lots of water changes, whatever builds up causes the water to go acidic over time (say within a month of no water changes, or less depending on fish load). I know this doesn't answer your question, but the main reason for your low pH may have little to do with the GH booster.

As far as whether low pH is bad or not.... the general consensus seems to be that it's ok. My co2 tank has a pH probably down in the high 5's or at least low 6's and everyone seems happy, fish and plants.

 

This is an interesting case. Can you tell me what is your GH and KH, in ppm please (tap and tanks).

I can't remember last time I have checked the pH... but I do test for GH and KH occasionally, which is in my opinion the important part of buffering the systems pH and binding acids.

My tap is also way too soft, and for that reason I added a fair amount of CaCO3 (couldn't find any Dolomite) into my soils (2 new tank), so they don't get too acidic over time.
Beside that I will also dose the GH-Booster every week.

Regards, Dusko

 

Ok, in that case, that sounds very odd. If the co2 tanks are at or above 5.5, that sounds normal if you have low KH. But in a non-co2 tank, 5.5 is pretty acidic. GH itself has no effect on pH, it's only the KH that buffers the pH. I add magnesium sulfate and calcium chloride to my tanks, it only increases GH and never affects pH. I'm not sure what else might be in the GH booster that would cause a pH drop.

 

My impression is that GH Booster (or Equilibrium) does not effect alkalinity (KH). I know that when I use Equilibrium I have to add Epsom salts to increase alkalinity.

If the above is correct, it's unlikely that GH Booster would have any effect on pH, since at any time that is closely related to the alkalinity level.

But I could be wrong, too.

Bill

 

Even if it were adding KH, that would only bring pH up, not down. Does anyone have the ingredients list?

Also....epsom salts don't increase KH either. KH is carbonates - i.e. calcium carbonate, sodium bicarbonate, etc. would increase it and possibly affect pH (bringing it up). Epsom salts is magnesium sulfate. The magnesium adds GH since GH measures magnesium and calcium only.

 

Is there a chance that the pH probe calibration was faulty? For example, to be a good calibration you need two different pH solutions, usually 4.01 and 7.01, as I recall. It is only if you can assume the probe is working correctly and just want to adjust the meter reading, that you can get by with the single point calibration.

 

Ummmmmm Sulphur or in the case above sulphates

Do I win a prize Tom??

Great site and info by the way.

 

How would the sulfates react in water to produce an acid?

 

The same way sulphur applied to soil will lower the ph of that soil with the aid of bacteria and moisture to form sulphuric acid. it can take quite some time for this to happen though. Aluminium sulphate would lower the water alot quicker if it were used.

 

I don't know enough about chemistry to understand it, but perhaps with very large concentrations of SO4 in water, sulphuric acid is produced? I'm wondering if the GH booster was dosed without premixing and allowing it to sit at high concentrations, if there would be a difference. I dose magnesium sulfate and K2SO4 in my tanks and have never noticed a pH drop from the sulfates (and I have little to no buffer in my water). But I dose straight powder, and in small doses compared to what you added to your premix. I wonder if you were to take a quantity of water (aged) and dose what would be considered a "normal" amount assuming it was a tank, and test pH before and after, if there would be a difference? If not, something is happening in that premix that's not happening normally, or that wouldn't happen if you dosed straight powder.

 

I just did a little experiment of my own. I had three test tubes, filled them all with tap water (which for me is close to distilled,

 

K2so4 should not alter ph but mgso4 can raise it and caco3 can in fact lower ph by the way of 'mopping up' hydrogen ions - no more, no less! There are a variety of ways to do this which can include calcium/lime - but it is certainly not limited to this.

Lime (CaCO3 - calcium carbonate) mops up hydrogen the following way:

CaCO3 + 2H+ → Ca2+ + H2O + CO2

But magnesium carbonate (with no calcium) can be just as effective:

MgCO3 + 2H+ → Mg2+ + H2O + CO2

Hydrogen is a highly reactive/aggressive cation capable of stripping other cations from their bonded anionic partners, e.g. (CO3)2-. Calcium, magnesium and other cations are merely passive passengers in the process of raising pH - it is their anionic partners that actually do the 'mopping up'.

Some unexpected results can occur though. For example, calcium sulphate (CaSO4) found in gypsum can react the following way in the presence of excess hydrogen:

CaSO4 + 2H+ → Ca2+ + H2SO4 + CO2

H2SO4 is sulphuric acid!! Therefore adding sulphate-based inputs (even with a calcium component) to acidic water can plummet pH levels down even further.


to adjust kh or alkalinity use bi-carb soda

to adjust gh and kh use calcium carbonate

 

I'm not a chemistry buff whatsoever, but I try to learn... this is probably oversimplifying it but I have to start somewhere.

So if there are extra H+ kicking around anyway, isn't the water already by definition acidic? Would the reaction of the excess H+ with the other things somehow make the water more acidic than it already was before? If so, don't more H+'s have to be coming from somewhere? How can more H+ be around to lower pH if we don't add any more H? Is this what you're saying Tom?

In my little experiment, the KH2PO4 made the water more acidic. I see an H there in the equation so this must have ultimately caused it in some way, right? The Plantex CSM+B did too, but I don't know the ingredients of this. The K2SO4 did nothing....because I wasn't adding any H? My understanding of this is far from complete....it's been way too long since chemistry class.