i hope i can ask this question here

i have 5 HDDs and 1 hdd i put temporarily outside.. *sigh..
is there any casing that suitable for 5 HDDs? i checked my casing now and it have 5 slots for HDD. but i think the space between hdd will be too close..then the HDD will be hot rite?

1 more..
is there any casing/box for hdd to put outside..haha..i'm not sure if this exist or not..that maybe use external power.. then i can add few more hdd..hehe