Fish outside their PH range.

[Tech]

Even beyond pH/GH/KH/TDS etc, our local water in the winter is ice cold, 50F on a warm day coming out of the tap, and the gas created in our pipes in the winter months plays havoc with the slime coat of some species of SA fish, such as chocolate cichlids. (H. temporalis) So I no longer keep them either, as I don't have time to store water in vats etc.

Gas created in the pipes? I've never heard of that. My water is a pretty similar temp and I haven't noticed any gas in it.

Thanks for the article on Hex btw, likely saved hundreds of fish with that one.

 

[pops]

this is true, say my water in summer when i do water changes I do not get micro bubbles on the sides of the tank, come winter when its coldest I do, and a long term cold snap, they will even form on the fish. cold water holds allot more gasses than warm, and for some fish this can be an issue. hence the need to run RO water.

 

[RD.]

Yep, and the colder the water, and the larger the water changes, the more bubbles in the water. Most fish no problem, but with some fish it will peel the outer layer of the slime coat off to what looks like big sheets of snot. In extreme cases it can cause far more serious problems, such as gas bubble disease.

http://www.ncbi.nlm.nih.gov/pubmed/9289892

http://www.advancedaquarist.com/2014/8/fish

 

[duanes]

You can tell when/if your water is saturated, or super saturated with oxygen or other gases by filling a glass with cold water. If its cloudy, and clears from the bottom up, it is saturated.
In winter I always sent water to sumps in stead of directly to the tank to limit problems. In Jan or Feb in Milwaukee, cold water could be 40'F or less, and because water in the pipes is under pressure, those gases are not released until it exits the pipe, even when mixed with warm water. As RD said, certain fish are more susceptible than others to as bubble embolism, or other problems from dissolved gases.