LT green anemone

[Klaus777]

I'm looking for some experienced keepers of these. I have been searching for days for an answer and came up pretty dry.
I brought an LT green anemone home last week (in my tank for 7 days now)and it is refusing to attach anywhere. It also always has its mouth open about the diameter of a pencil, sometimes a little larger. The tentacles are only about 1.5 to 2 inches extended during lighting hours. So that's the bad signs. The good signs are that it does inflate it's disc to a good 6 to 7 inches diameter and it has eaten for me twice (raw table shrimp).
What I would like to know is has anyone ever had success with a nem that hasn't attached?
Has anyone ever had similar issues and had the nem turn around for the better?
I just want to figure out if this is a fruitless effort and if I should just cut my loses before it starts rotting and taking my system down with it.
Also, this is not my first anemone. I have had a RBTA for a year and a half and have great success with it and it is doing fine in the tank.

[Toddrtrex]

First things first;

What size tank?
What lights? (( did you acclimate it to your lights? ))
Did you get it from an LFS, or shipped?
What are your parameters -- with numbers please
How long has the tank been set up?
How deep is your sandbed? (( Macrodactyla doreensis are sandbed dwelling anemones ))
Is the BTA in the same tank? Do you run carbon?

[Klaus777]

The tank is a 45 gallon cube hooked up to others tanks and sump totaling over 200 gallons. The system is over two years old. No Carbon being run. it is in the same tank as the RBTA
lit by metal halide 250Watt 14,000K. I acclimated the anemone to the lighting by the use of a few pieces of egg create over the course of a few days. I got it from a LFS and drip acclimated for 1.5 hours while maintaining temp of 76F. the tank is bare bottom but I placed a container in the tank with 4 inches of Oolite sand and set the anemone on/in it.
Pars -
Salinity - 35ppt
pH 8.2
phos - 0
ammonia - 0
No3 - 0
No4 - 0
Cal - 425ppm
Alk - 8.4dkH
Mag is high at 1500ppm but with no visual effects on any other inhabitants of the tank

[Klaus777]

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