I have been having issues with corals in my 16 gallon nano tank and I am not sure why. This is my first tank and I recently added 4 new corals last week. For the first 1-3 days, my 2 Zoas were opening up almost completely without too many problems, however, they stopped opening about 2-3 days after and have not opened fully since. I just did a full test test yesterday and parameters are good, I had to add a lot of magnesium and calcium supplements due to low magnesium and calcium levels. I did a few big water changes and had to increase temperature from 23 degrees celcius to 25. Now my tank parameters have been good for the past couple days. I don’t really have any problems with my candy cane it seems. My Duncan stopped opening yesterday and his tentacles have visibly shriveled up since I got him. I am suspecting too much light but I am not sure since I do not have much experience. I am planning on lowering light to 7 hours. However, I am worried about stressing the corals any further. My invertebrates have all been happy and don’t seem to be having any issues.
Tank parameters -
Ammonia - 0 ppm
Nitrite - 0 ppm
Nitrate - 5 ppm
Magnesium - 1400
Calcium - 400
Alkalinity - 12
Salinity - 1.025
Temperature - 25 Celsius
Lights - Coralife Biocube size 14 lid, 10 hours
Ph - 8.2
This is what my coral looks like now. Pictures of them being open are from last week.
![88FC97D4-5B97-47F1-AB52-F20E639B7623.jpeg 88FC97D4-5B97-47F1-AB52-F20E639B7623.jpeg](https://test.reef2reef.com/data/attachments/2436/2436762-1495ed1333cbe0f11f7e73cb7cf1f861.jpg)
Tank parameters -
Ammonia - 0 ppm
Nitrite - 0 ppm
Nitrate - 5 ppm
Magnesium - 1400
Calcium - 400
Alkalinity - 12
Salinity - 1.025
Temperature - 25 Celsius
Lights - Coralife Biocube size 14 lid, 10 hours
Ph - 8.2
This is what my coral looks like now. Pictures of them being open are from last week.
![CC2E9695-B696-4B20-AD64-858B70BBC826.jpeg CC2E9695-B696-4B20-AD64-858B70BBC826.jpeg](https://test.reef2reef.com/data/attachments/2436/2436744-b75af951c9a3a1ab725e62fefa17aa16.jpg)
![9CD4FCB8-7AB9-4B84-8E85-36ED747AA823.jpeg 9CD4FCB8-7AB9-4B84-8E85-36ED747AA823.jpeg](https://test.reef2reef.com/data/attachments/2436/2436745-704eb5262ec42e6ad3a825462a4705d7.jpg)
![50CB5F41-8661-4A63-98F3-093EDB3FD162.jpeg 50CB5F41-8661-4A63-98F3-093EDB3FD162.jpeg](https://test.reef2reef.com/data/attachments/2436/2436746-1c0fec4d361039fc7a67232cd43d11ae.jpg)
![E82F4D10-8B32-4E5E-8296-AA5E41004E13.jpeg E82F4D10-8B32-4E5E-8296-AA5E41004E13.jpeg](https://test.reef2reef.com/data/attachments/2436/2436760-b09b994fc002f1ea4663b736b557d2f1.jpg)
![436B4DA3-87B1-4CA3-BA71-BA337F2A77FB.jpeg 436B4DA3-87B1-4CA3-BA71-BA337F2A77FB.jpeg](https://test.reef2reef.com/data/attachments/2436/2436761-af3e337524b0f70f3efd490abefcca98.jpg)
![88FC97D4-5B97-47F1-AB52-F20E639B7623.jpeg 88FC97D4-5B97-47F1-AB52-F20E639B7623.jpeg](https://test.reef2reef.com/data/attachments/2436/2436762-1495ed1333cbe0f11f7e73cb7cf1f861.jpg)