Yellow star polyps turning brown!!!

[Giancarlo_Flex]

So ive had these yellow star polyps for 5 months. They are now slowly getting thin and their tubes are turning brown. What do I do? 0amm 0-nitri 40-nitra. 580 calcium 161 KH

 

[vetteguy53081]

So ive had these yellow star polyps for 5 months. They are now slowly getting thin and their tubes are turning brown. What do I do? 0amm 0-nitri 40-nitra. 580 calcium 161 KH

This is nearly the true color while they are called yellow are more gold in tones. You have bubble algae which May suggest elevated phosphates, something to check.