[Iraf]

blue hippos need atleast 90g when matured

34g will only sustain it for about it's first 6 months of life if your lucky and that thing will have insane nitrate problems

Cleaner shrimps with any tang is almost a must since their a scaleless fish their very susceptible to ich and the shrimp will help keep them from getting it badly

Best advice, think about taking the tang back, or make arrangements to give it to someone with a larger tank, or use this as a good excuse to upgrade