What are your experiences with Dartfish?

[Zionas]

Hi all, recently I have taken an interest in creating an Okinawa / East China Sea biotope and I am looking into a peaceful, second fish apart from my Pajama Cardinals. This has led me to discover the Scissortail, Blue Gudgeon, and Zebra Dartfish. I would like to keep a group of 4-6, maybe even mix species. I've never been that attracted to the Firefish and heard they don't do well in groups.

I know they're peaceful to other fish, my tank will hopefully be completely covered and knowing how skittish they are if I think I'm OK with these fish they'll be the first fish in the tank.

Any difference in hardiness between the three species?

Are they hard to feed? I read somewhere they need an established refugium like Mandarins do.

Will the following selection of tankmates cause them trouble?:

-Halichoeres Wrasses

-Shrimp gobies

-Hawkfish

-One Spot Fox Face

-Yellow Pyramid Butterflies

-Ocellaris Clownfish

-Cardinalfish


Also, about their burrowing habits, I plan to have a 2-3" sand bed (for my gobies and Halichoeres too) but I heard they can't make their own burrows like the gobies and wrasses and need PVC pipe?

Thanks.


Also, regarding their lifespan, are they known to be able to live over a decade like some shrimp gobies?