Phosphate levels

[DraggingTail]

I notice slower growth and less coloration at the lower end of the phosphate levels.

For example, for a few months I was hovering between .012 and .086 with an average of .055. I notices slower growth and lighter coloration. Now, I have brought my phosphate levels back up to 0.15 to 0.2 where they were before and notice faster growth and darker coloration on the coral which indicates that the symbiotic algae are happier....

Is this correct? Do other notice this a well?

Thanks,

 

[Spare time]

You will get darker looking corals with higher phsphates due to increased zooxanthellae.

The only downside I can imagine is that eventually they can become more brown looking and that the coral may be competing with the zooxanthellae for carbon or other elements that are not normally competitive between the two symbiotic organisms. However that is more of a guess based off of some other knowledge as to why higher alkalinity decreases competition for carbon between the two.


I personally keep mine somewhere between 0.1 and 0.

 

[Uncle99]

I run No3 at 6ppm and PO4 at 0.2 like you.