Dying hammer garden?

[Zigaz]

Ive got about 15 heads of hammers and they are all looking great i bought this hammer garden and after couple of days that one hammer is gone! But ive just noticed as you can see on pictures where i circled it there are couple new heads around it and can see tentacles should i leave it and hope its going to grow? Thanks

 

[Gumbies R Us]

Need more information about your tank
Parameters and what you are testing them with
Light and par
Flow
Photo under white light
Anything that could be bothering them
What about the rest of your tank?