King Midas Shrinking Away

[Jizu Puentes]

Hello all I need some ideas on why my colony of King Midas are shrinking away. My tank is an 110 gallon lit by 4 T5s. I tested the parameters after I did a water change Tuesday and they read
Ca-460, Mg-1520, Kh-9.8, Phos-0.25 Nitrate, Nitrite and Ammon a are zero. Temp ranges from 79-80.4 the colony is at mid level in the tank under medium flow. Here is the colony

I'll retest the parameters Saturday. I had this happen to a colony when I started with a 29 gallon and only one polyp survived then.

 

[saltyphish]

Your nitrates are zero and your phosphates are .25? If that is correct the .25 phosphates are high and some nitrates are good around 5 ppm or less but you do want some.

 

[Jizu Puentes]

Oh yes I recently added a large dry rock to one side of my tank and I'm pretty sure that it is causing the phosphate rise. Would the phosphates bother the zoas?
Also Phos, Nitrate, Nitrite and AmmoNia are tested with API tests so they may not be accurate haha

 

[saltyphish]

I believe high phosphates can bother even zoas. I would not say your off the charts though. Api phosphate test kits are not very accurate ime. I use a Hannah phosphate meter instead, very accurate.

 

[luke33]

How did you test for phosphates? The only real way to get a good reading is to use a hanah checker. If they are .25 that's pretty high and I have never had a lot of luck with alk around 10 and zoa's. But if you just added a dry rock I would imagine that is the phos cause as well.

 

[Jizu Puentes]

Yea I definitely think it is the rock. It is about a 30lb rock so it's pretty sizeable. I thought my macro algae would consume any extra phosphates but I guess not. I've been doing weekly water changes so hopefully the excess phosphates are removed soon. Here is the rock I speak of.