How much does ionic imbalance affect fish?

[Myka]

We always talk about ionic imbalance in reference to coral health, but what about fish? We've all seen those dingy marine aquariums at restaurants that get one waterchange every 3 years. I assume NO3 and PO4 levels are a bigger concern, but what about all the other ions that make up saltwater?

Since the four most abundant ions in seawater (Na+, Mg+=, Cl-, SO4--) comprise 97% of the total weight, any changes in other ions will not significantly impact specific gravity.

Is there any affect, direct or indirect, on fish if these "big four ions" are all out of whack? Do calcium and KH affect fish (besides impact on pH)? Do any of these affect osmosis?

Any references I can read? I can't find much!

 

[Randy Holmes-Farley Verified Community Expert]

I've never seen studies of this type.

 

[Myka]

I've never seen studies of this type.

Bummer. Thanks for responding.