Fish Adaption To Acid Levels

[Martin e]

Hello Everyone

I’m interested in trying to understand the science behind the adaption of fish to acidity levels. Some fish species are able to live in water that is effectively poisonous to other fish species. For example, a fish adapted to thrive in relatively acid water conditions might not even survive in alkaline conditions and similarly a fish adapted to alkaline conditions might perish in acidic water. My question is why? What are the key differences between the species that can survive acid conditions and those that can survive alkaline conditions?
Are the differences structural, for example difference in design of gills or such like, or are the adaptions biochemical such as the fish having enzymes that can perform the necessary chemical processes, or is it a mixture of the two?
I believe that water acidity can affect what nutrients are available in the water so how does a species of fish overcome a lack of such nutrients? Is it able to somehow extract the nutrients that other fish cannot extract or does it adapt by making do without such nutrients; perhaps substituting different nutrients to make up for the deficit?

Thanks for your interest and any advice you are able to give.

Martin

 

[nurglespuss]

Hi there,

there has been a lot of research done on pup-fish (small fish that survive in very harsh conditions), it would be worth starting your search there.

These things can survive (dependent on species) in very hot/very cold water, water with very low oxygen, high sulfur water, acidic/alkaline etc.

 

[StandbySetting]

It's not really to with PH, but more KH+GH, it's mineral related, but obviously KH has an influence on PH, especially metal ions such as Mg[sup]2+[/sup] and Ca[sup]2+[/sup], K[sup]+[/sup] etc, I don't the exact sciences behind it and it may be worth posting in the scientific section, but my guess would be that it affects osmoregulation - ion transfer across gills to regulate water content, because water with a higher PH will have higher a concentrations of Magnesium, Calcium, Carbonate and other ions, the fish will take on more minerals due to the difference in concentration, resulting in a difference in osmolarity.