Extending Ex495 Drive Pool Via Esata?

Hi,

Looking to add more storage to my ex495. Want to look at one of those enclosure things using either the USB or esata. As ever, lookign through forums only getting me more confused! port multipliers; JBOD, RAID etc etc

So, any simple steps or reccommendations?

Would prefer enclosure able to accommodate 3TB drives if poss, but could do 2TB ones

Is there on you can buy + just plug into the esata port at the back?

For increased pool - not for backup etc etc so would have to be running 24/7

Cheers

Steve