pinky93

I am tryin to lower my pH which is 8.4.I was wondering if rain water would do the trick

Shawnie

I dont think you would want to put rain water in your aquarium...who kows whats in our environment!

pinky93

lol that's true...I jus thought it would be neutral but i was wrong.I tested it and it's 7.6

sirdarksol

That's actually really odd for rain water. It's usually a bit more acidic.

You can more easily mess with the pH of rainwater, however, since it doesn't have the buffer layer that tapwater with a high pH usually has (I'm in the same boat, and am thinking the same way). If you collected rainwater in a barrel and kept a pillowcase full of peat moss in it, you'd be able to lower the pH significantly. Then you could mix it with tapwater to get the desired pH prior to adding it to your tank.
It's likely that, whatever your water source, the same stuff that's in your rain is in your drinking water (scary thought, neh?). Aquifers (with your pH, I'm guessing this is where your municipal water comes from) are refilled by rainwater seeping through the ground. The ground can filter the water to some extent, but the toxins slowly leach down until they reach the aquifer. Reservoirs are, of course, filled by rain water. Water drawn off of a river, ultimately, comes from rain water, etc...

The biggest issue with doing things this way is that you need to make sure that, once you get your pH to the level you want it at (and do that slowly, mind, or it will be bad for the fish), you need to make sure that the water you add is always the exact same pH. If your source of rainwater runs out (don't know what winters are like where you live, but I'd have to melt snow to get "rainwater" for four to five months of the year), you've got to use distilled or RO water to maintain your pH.

pinky93

ok...will bottled water help?

Chief_waterchanger

That depends on whether the bottled water is spring water, distilled, or reverse osmosis.

Spring water: Is pretty much like water out of the tap of the location of the bottling company. (Generally runs 7.0 to 7.4 in the few we've tested in the USA.)

Distilled: Should be 7.0, however, it has no buffering capacity, and would be greatly affected by decaying organic matter. If used exclusively it is prone to sudden pH shifts. Buffering capacity means the amount of ions in the water. Acids can bond to things other than the water molecules themselves. When the acids or alkalides bond to water molecules the pH changes in your water. By having a decent buffering capacity the acids and alkalides bond with the molecules other than water, which are the ones that give the buffering capacity, usually calcium, you are kept from having sudden pH shifts.
Example: 1 drop hydrochloric acid per liter of distilled water will drop the pH by 'x' points. (Hydrochloric acid = pH 3; Distilled water = pH 7.0) Spring water which, in MOST cases has some sort of buffering capacity, a drop of hydrochloric acid would probably not show a measureable change in pH. That is due to the acid ions bonding to the molecules that make up the buffering capacity.

Reverse Osmosis water: Is the middle ground. While RO water does not have buffering capacity of spring water, it does have more of a buffering capacity than the distilled. So it is like a tamed down version of untouched water. (They use pressure to push water through a membrane. That membrane takes MOST molecules out, but not all.)

This post was brought to you by my typing and Dino's scientific knowledge.

sirdarksol

Aside from the pH issues with distilled water, it can also kill fish because fish's cells were made to have a certain amount of minerals in them, and distilled has none. Osmosis will try to even the water percentage out, which isn't possible, and osmotic stress can kill the fish. For a similar reason, it is suggested that you not drink straight distilled water, at least not in large quantities. There are additives that can deal with this, however. They make them to mimic different freshwater scenarios.
RO water that started out with very little minerals or that goes through a very high-power system (with the extra stages in place) can be very similar to distilled water.

Thanks for the extra info Dino and CWC (you corrected a piece of misinformation that I was given a couple of months ago.)

pinky93

Thanks guys, you really kno ur stuff!