Sand dwelers fish

I had problems with sand dwelers fish, all of died, and i suspect of a coral banded shrimp as the killer, i have remove the coral banded and want to try some sand dwelers fish, tank is 140g with 45 sump and 1.5 years old.

I will like to add mandarin dragonet, red scooter blenny, lawnmower bleny and some shrimp goby with its shrimp.

Is there any problem with compatibility with this fish??

An I gonna need supplement pods for the mandarin and scooter blenny??

 

Dragonets are compatible with gobies but need to be placed with other dragonets and blennies with caution.
Blennies, as said, are cautionary friends with dragonets and also other blennies. However, they are perfectly fine with gobies.
Gobies should be placed with other gobies with caution.
But from the large size of your tank, all these fish should most likely be alright together as they will have room for their own separate territories.
A handy tip is that the less the fish look like each other, the less they will fight.
You will most likely need supplement pods for the mandarin as they are picky eaters but I am unsure if you will need them for the scooter blenny. Hope this helped.

 

Shrimp goby (If you want more go with a pair) w/ shrimp will be fine
Add the dragonets when the tank is around 1 year old (along with fuge) before the blenny, there may be a bit of chasing but IMO you'll be fine.