Cleaner shrimps are very cool! Brittle Stars are too! But I would use caution since that brittle star needs to use a crevice in the rock (most likely a burrow) during the day especially. So as long as your fish have space and hiding places, as well as the star then you should be good. The serpent and brittle stars are usually very peaceful and hardy! If you find a harlequin serpent star or a species that gets smallish at full size then I would recommend getting that.Thanks for the tip! I have a national product, probably worse than stressguard, but it helps to deal with the stress.
And yess, I will with a sharknose goby or a blue neon, the cheapest, I guess, and at the end I will see if its possible to add one more or if it looks already crowded.. because Im also looking for to add a cleaner shrimp e a britle star! Thanks