Reef Chemistry, K and Na importance

[New Jersey REEF]

Question about reef chemistry and importance of these two elements

I was looking to purchase ion director which will test Cal Mg No3 Na and K parameters.

I have couple of questions about this.

1. What do corals use potassium (K) and sodium (Na) for? I know it’s a complex question and requires some understanding of how chemistry works. But I hope someone can shine some light on this for me.

2. What are some negative affects of lacking those elements in the reef tank or say we have too much of concentration of those elements?

Thank you

 

[Randy Holmes-Farley]

Sodium is the second most abundant ion in seawater (10,000+ ppm) and the most abundant ion in living creatures (like human blood). It is critically important, but exact levels are not. Seawater contains more than creatures need or want, and they generally try to pump it out.

A reef tank at normal salinity is not lacking in sodium.

Potassium (400 ppm) is also used for tons of cellular processes, especially membrane potentials, nerve conduction, etc. It can become depleted in reef tanks (or not; mine never did) and is worth monitoring. It is generally present inside cells higher than the surrounding fluids (blood, seawater, etc.), and cells actively take it up.

 

[nereefpat]

The only reason I can come up with for monitoring Na would be to track salinity.

I would think that K+ would be taken care of with even the most conservative water change schedule. If not changing water, it might be something to keep an eye on.