PH too High in New Tank (cross-posted)

[Roan Art]

I wasn't confusing the two. They were two separate points. Guppies like hard (or should I have said TDS? BTW what is TDS?) water AND just about all the guppy sites, and guppy breeders, ect, recommend adding salt to guppy tanks (up to one teaspoon per five gallons).
,

Adding salt does not make hard water. It makes salty water. You are just adding sodium to the water and as with your water softener, it does not make the water hard at all.

This is what I was trying to explain earlier. It's is another common misconception in the hobby. If you want to make the water hard, you add Ca and Mg -- the same stuff your water softener takes out of your tap water -- and a lot of other elements as well.

People add salt to the water because a percentage of the water in question does contain salt, however in most cases -- such as with livebearers and Rift Lake cichlids -- salt is only a small fraction of that content. They try to emulate the "natural" setting of the fish by just adding salt. It doesn't work quite that way and in the long run it will negatively impact the fish.

Here's an example of a quick recipe that RTR posted:

http://www.aquariacentral.com/forums/showpost.php?p=313678&postcount=7

His recipe actually has no salt in it at all.

Roan

 

[Hypatia]

Roan,
I think I understand the confusion here.
It sounds like you knew, which I didn't, that the reason guppy sites tell people to add salt to the water is because *they* believe that this makes the water hard... is that right?
I didn't know that.. So when you were saying that salt doesn't make the water hard, (bear with me here ) I thought, you thought, *I* thought that salt makes the water hard. I didn't. I didn't acctually know why the sites said that guppies like this... I just knew there was a general consensus among many guppy sites that they do.

Everyone,
So I looked up some of the sites to see if maybe this was the case. I found several different reasons actually, and a whole lot of sites that didn't give any reason. Here is one site that summerizes several I found..

Sea salt should also be added to your tank water. I use one teaspoon per gallon when I initially set up a tank, then about once a month make a partial water change, adding the same ratio of salt to the new water. Salt increases the ability of water to carry oxygen, helps fish produce good protective slime coats, and adds minerals to the water that fish absorb through their skins. These minerals aid in bone and tissue growth. Salt also provides a hostile environment for fungi and parasites, and so helps prevent disease beyond the natural protection of a good slime coat.
From http://www.aqualink.com/fresh/z1-guppy.html

I do not know enough chemistry to know if any of these reasons are valid.. again I don't use salt in my guppy tank, so I've never been all that worried about it. But now I am curious. I wondered if you or Happychem, or someone else in the know could clearify.. I mean, if salt is very bad for fish, where did people get the idea it could do all the stuff stated above and that is was a good thing in the first place. I assume there was some basic idea that got misunderstood like the hardness thing... dose anyone know?
This seems like a new thread, so I am going to move it and post the link in just a sec.

 

[happychem]

Salt increases the ability of water to carry oxygen

This is completely wrong, I'd call it an outright lie, but I think that it was spawned out of ignorance. The most basic gas solubility rule is that the solubility of a gas decreases with increasing electrolyte content. Why? When a salt dissolves in water, water molecules arrange themselves around the ions to reduce the charge in solution. Water molecules are polar, meaning there's a difference in charge along the molecule - kind of like a magnet works. The hydrogen atoms in water are slightly positive, the oxygen atom is slightly negative. So when you add a salt like NaCl, it dissolves into Na+ and Cl-, water molecules surround these ions so that the oxygens face the Na+ and hydrogens face the Cl- (these are called the "waters of hydration). From a physical sense this means that the amount of water available to dissolve gases has decreased. Hence, solubility decreases with increasing salinity.

As for developing a slime coat, salt is an irritant. By irritating the skin and gills of the fish it stimulates mucous production. This can be useful at specific times - say in times of injury or in fighting Ich. However, as a full time doseage, an irritant is an irritant, and this means stress. So no, it should not be dosed as a regular additive.

Absorption of minerals? Fish may be a little better equipped for this than other higher beings, since they're emersed in the medium. But generally higher beings are not able to derive significant quantities of nutrients from their surroundings because there are too many cells which are not in contact with the medium - hence circulatory systems. Also, the concentration of these minerals is very low, usually not sufficient to satisfy metabolic needs. This is why we get most of our nutritional requirements through food. However, it may be different for fish because they're bathed in the medium. I'm skeptical about this, but I can't rightly say that it's wrong.