I don't mean to be a stick in the mud, but you don't have a true linkia starfish. You actually have the
Linkia guildingi, which is not a 'True' Linkia starfish. These are commonly known as the 'Orange Linkia,' (dispite that it's not a true linkia), or the 'False Linkia Starfish.' These starfish are much more hardy to keep in the home aquarium, and prove to be much easier to care for, compared to the Blue or Purple Linkia Starfish (linkia laevigata).
All starfish have extremely sensitive hydrovacular systems, which are extremely sensitive to even the slightest change of pH, temperature, and salinity. Therefor, acclamation should exeed 4 hours using the drip method for aclamation. Otherwise, it may cause damage resulting in Loss of limbs, shrinking, and slowely dying off. You probably already know this anyway
Anyway,
That's a very nice Starfish Sammy! Looks extremely healthy! The purple lobster also looks very healthy, and full of coloration. I doubt you will be seeing him too often in your setup though, as these are nocturnal, and will come out only at night (for the most part), hunting for food.
Graham