can i add to current setup?

I really want to add 1 or 2 Bristlenose Plecs to my set up -  Currently have a 240 litre roma with 3 x marble angels,10 x zebra danio,5 x lake kutubu rainbow fish and 1 x red tail black shark.   Will the bristlenose fit in? will the shark or angels hassle it? how many should i get? or am I...