Yeah I highly recommend a big fermenter for this from now on. My 5.5g batch had about 2-3 gallons of krausen on top. So my 10G fermenter was plenty and didn't have one bit of blow off.
Also the other thing I decided go with for next time is hopshot at 90min instead of hop pellets. Will keep more beer that way instead of using 5-6 oz of hops.