vinegar and pH

[jdsunflower]

As an FYI,

Some experts (e.g., Walsted) recommend using vinegar as an easy way to lower pH in a planted tank--but a caution from my own accidental use with non-planted tank: vinegar breaks down into acetic acid which plants eventually can use as carbon dioxide as it further breaks down. Without plants, too much co2 (well if you have to drop the pH as much as I do).

To make matters worse, vinegar to lower pH mixed with bicarbonate soda as an alkaline buffer (which many use) creates 'a volatile form of CARBOLIC acid that quickly precipitates into carbon dioxide'. Yikes.

I lost 5 harlequin rasboras before figuring this out, and almost lost my 5 corys. I'm thinking that they probably survived because of the labyrinth organ.

Now I'm using a smidgen of pH down, until I can slowly acclimate my fish to a higher pH. Can anyone tell me just how high is too high for tropical fish? Tap pH is close to 9 and gh and kh are below 2, and I'd rather avoid r/o expenses if I can...but not at the cost of fish lives. I figure if I can get them used to 7.8 I'll be happy with far less use of chemicals...
JD

 

[Lager]

That is some interesting tap water you have. a KH of 2 and a PH of 9. I wonder what else is in there acting as a buffer. Have you tried mixing the tap with RO/DI water?

 

[jdsunflower]

no, due to $$. Someone told me it's because the city is using phosphates to increase pH, whereas it is naturally soft and acidy.
I know some people add phosphates (yes on purpose), I wonder if this will spare me at least that!

 

[OasisKeeper]

That is some interesting tap water you have. a KH of 2 and a PH of 9. I wonder what else is in there acting as a buffer. Have you tried mixing the tap with RO/DI water?

Exactly my thinking. These are really whacky readings and therefore likely incorrect. This implies a lot of sodium phosphate or organics or something. So I'd say step #1 is:

What test kits are you using? Let's make sure these readings are correct before you add anything more to your water.

PUT THE PH DOWN BOTTLE AWAY! (channeling Mel Brooks).

Did you do that? Good... Let us know eh?

Edited to add: Call your local water district, tell them what you are doing, and ask for their current tests. Most water agencies are pretty forthcoming.

 

[jdsunflower]

various liquid reagent kits as I hoped it was a misreading... (API and Hagen, wide range, low and high kits, brand new). These readings aren't new--I've had aquaria for years and it's always been an issue. The local fish stores keep tetras in pH of 6, so I know people are having to do something with their water. I wondered why the hobby wasn't bigger in this city, but I wonder if this might be part of the reason...phophates used in the city water...
How high of a pH is acceptable for tropical fish, anyway?

 

[jdsunflower]

I like the suggestion about contacting the water agent. Thanks! Will do. It's a 40 g tank, so I dread to have to start buying water (esp. without a car).

 

[OasisKeeper]

I like the suggestion about contacting the water agent. Thanks! Will do. It's a 40 g tank, so I dread to have to start buying water (esp. without a car).

Yah, and if you manage to get the lab guy on the phone, he can probably tell you the easiest way to fix it as well. They to water for a living (TM).

 

[Ruadh]

Just as a point of disscussion, if phosphate is what is raising the Ph, then would a phosphate filter or something like Phoslock be a reasonable thing to lower the Ph?


Rick

 

[jsoong]

People add phosphates to lower the pH. pH down is phosphate based.

If you have just free phosphate (ie add H3PO4), that would buffer the water to pH of 2.4 or so. Other phosphates have differing buffering properties (NaPO4 is around 7.5, eg). At any rate, I think using a phosphate filter is unlikely to change pH much (assuming you have other buffers around.)

jdsunflower - you might try checking the net for your water result. My water co. post water composition tables on the net. One reason your water is that screwy may be due to the water co adding stuff to bring up the pH. Soft water is fairly corrosive to pipes, so the co. brings up the pH with NaOH or other stuff.

 

[OasisKeeper]

I don't think it's all quite so straight forward j... phosphoric acid has pKs at 2 and 12 .. check this out...

Phosphate Buffer Calculator

Plug in a Ph of 9.. takes a fair bit but you can hit it. Obviously depends upon the other ions as well, which we don't know. But the water guy probably does.

This may also be the reason we have trouble explaining high PHs in some of the other discussions.

 

[tomherndon]

the tap numbers reported are a bit screwy, but the issue is probably the organics applied to control microbes in the water column for consumers. Chloramines, etc. It's not just pH that controls those critters, the other parts of the molecules are often the lethal component and the pH change is coincidental.

I wonder if you could lower pH with a different household acid like vitamin C or tartaric acid (cream of tartar).

the vitamin C actually has a higher first ionization than the acetic acid, but the tablets likely have several other ingredients that serve to buffer the acid. It's added directly to water to remove iodine following iodine tablet treatment for camping. Of course, sold as an iodine remover it comes at a higher price (which might be due to an increased concentration per tablet OR savvy marketing).

any heavily-degreed analytical chemists out there?

 

[jdsunflower]

thanks for all this information!
lots to think about.
The pH down states clear it is phosphate free. Apparently there is sulfuric acid in there () but my fish certainly seem a lot happier than when I was using vinegar, plants or no, given that it is not stable in the tank.
I'll try contacting the local fish society as well. Their site is far from this one as far as tone, etc. I noticed everyone here is in Ottawa is into cichlids, I thought it was just a popular trend, but maybe it's a compromise.

 

[jdsunflower]

a big thank you for this help. I have struggled with this extremely frustrating situation for (it seems) ever and no one could seem to suggest an explanation, let alone a solution except 'leave it alone'. On the other hand no one seems prepared to say I should keep my (acid pool type) fish in the pH of 9!
How high is the highest reasonable pH for catfish, tetras, danios, etc? VERY hard for me to believe I should just ignore the pH here.
Monique

 

[DSenn]

Lime I said, I got my R.O. unit from Foster's and Smith, 135 dollars. That isn't too expensive for anyone in this hobby.

 

[jdsunflower]

The price is indeed quite reasonable. Do you have to have access to a separate water tap for this, as it sounds like it goes for hours? I am in a tiny condo, so only have sink and bathroom taps, for instance.

 

[Purrbox]

There are some RO Units that can be hooked upto a faucet with an adapter peice. I don't know the exact name of what's needed or have any examples right of the bat, but it is something you might want to look into.

 

[jdsunflower]

thanks for the suggestion, I'll look into that.
Monique

 

[DSenn]

You can hook up your R.O. unit anywhere, basically. The unit is easier to use if screwed into a fixed location, but you don't have to have it like that. You can hook it and unhook it to your faucets whenever you wish, but yes, it does take some time to make the water. I have a 50 gallon per day unit, and it takes about 2.5-3 hours to make a solid 5 gallons. But really, a 50 gallon per day unit is all you should need.

I mix my tap with my R.O. water, which doesn't seem to be an option for you considering your tap is wacky, so you will have to use buffers. Buffers can be kinda wacky too, so be prepared for that before you buy a unit.

 

[jdsunflower]

that's very informative, thank you.
Monique

 

[OldMan]

Another way to go with RO is to connect a drinking water RO to your kitchen sink. They come with a storage tank that you use when you want a glass of water to drink but it makes it easy to have as much as 3 gallons of water ready to go at any time. It connects under the sink and I put the tank in the corner of the kitchen cabinet that you can never use because it is so hard to get at. That way it doesn't use up any useful storage space. The water comes back to the sink through some tiny tubing and goes to a separate faucet for drinking water. I just fill gallon jugs from that faucet whenever I am getting ready for a water change. If you use straight RO water, there will be none of the minerals in the water that your fish need. What that means is you need to add minerals to the RO water before you use it for your fish. There are companies that make a mineral mix just for that purpose. One such product is called RO Right. It recommends different amounts depending on what kind of fish you are keeping. The minerals also provide some buffer to the water. Since we have installed a system like that in our home, nobody in the house drinks straight tap water any more but my tap water is good enough for all but the most sensitive of my fish. Those fish get an RO / tap water mix. I do not have crazy water like yours or I would probably use RO with RO Right on all my tanks and forget the tap water.