Hi all,
Yes and no unfortunately, it is back to the <"
unknown unknowns"> and freshwater being both:
So now we are really at <"
horses for courses">, and fish (and plants) adapted to hard water aren't going to have the physiological adaptations to survive in very soft water. Some people will argue that <"
fish will adapt to the situation they are placed in">, but I don't subscribe to that view. Personally I use fish (and plants) that naturally occur in <"
water with similar chemistry"> to that which I can provide.
Because water is a very efficient solvent soft water will always be "tannin stained" with humic substances and <"
it is these substances"> that provide the <"
buffering system in very soft water">*. If you placed most fish into DI water? Osmotic effects are going to do for them fairly quickly as they lose salts to the surrounding water and can't replace them.
*Morris, C., Val, A.L., Brauner, C.J. and Wood, C.M., 2021. The physiology of fish in acidic waters rich in dissolved organic carbon, with specific reference to the Amazon basin: ionoregulation, acid–base regulation, ammonia excretion, and metal toxicity. Journal of Experimental Zoology Part A: Ecological and Integrative Physiology, 335(9-10), pp.843-863.
Tom (
@plantbrain ) is <"
right about pH meters">, after that I'm guessing that this really relates to water without any humic substances. This isn't a criticism of Tom, just a reflection that he comes from <"
a very different place"> as a scientist, a place where ecology (and shades of grey) aren't really relevant.
cheers Darrel