It's just the branching dos that are loosing color. Don't know the names, but it was green, went to brown, lost a little bit of tissue and is now stagnant.
A bonsai Garf lost all color and is going pale, afraid it will loose all tissue any day now.
But the stag horn seems okay and the Seasons greetings is great.
Easy way to understand and remember the concept of nutrients and sps
Natural levels of symbiotic algae in sps tissue is brown colored and offers sun screen to the coral as well as nutrition. The zoanthelle utilize some phosphate and nitrate as a food source so with low levels or ultra low levels the symbiotic algae population recedes. This reduced population exposes the coral tissue color hence the pale or brilliant color some achieve.
Without supplementing amino acids or other food sources for the coral to consume from the water column the coral will decline in health from lack of natural food produced by the zoanthelle.
This is how you go about getting better or brighter coloration in sps corals.
You have to be careful with powerful lights and higher alkalinity while choosing to color up sps.
Achieving faster growth with higher alkalinity the coral needs more nutrition / organics to keep up with growth rates being faster. Trying to achieve great color and fast growth is how you get burnt tips, tissue loss or dead corals
This is why low nutrient especially ultra low nutrient systems run a more natural alkalinity level
To try and achieve both fast growth and great color is really keeping your water parameters on the brink of instability for the coral.
A good balance of both can be achieved as described above in another post by keeping a small amount of phosphate and nitrate the corals have a food source to replace what is missing from the symbiotic algae.
I find in my system that all the coral benefit from a little amino acid adittion while maintaining good growth and color.
Hope this helps understanding the mystery
Good luck and happy reefing
BluewaterLa / Mike
