Reddit reviews Eagle Brewing FE650 FermWrap Heater

fermwrap is my choice of heat. works great and keeps the whole chamber warm. I usually wrap it around the newest beer(along with the temp probe) and let the older beer ride!

I have a 5 gallon crock (likely similar to yours) that I've been running for a little while and love it. Consider having it professionally drilled by a tile installer or similar contractor (with a diamond hole cutting bit and a water cooling system), and installing a spigot like I did: https://www.reddit.com/r/Kombucha/comments/6ab9iw/added_a_spigot_on_my_stoneware_crock/
It will make your life SO much easier, whether you use the batch method or continuous.

Also, to make the 2F flavoring stage easier on this scale, consider flavoring in carboys or a similar container with an airlock that can release excess pressure. Then you can strain before the bottling stage and not have to strain when serving. I talked about the process a bit here: https://www.reddit.com/r/Kombucha/comments/6ae9gw/natural_flavoring_test/dhfg9a7/

For a 5 gallon crock, you'll only need a 3 gallon carboy. Here's mine with fresh raspberries, puréed: http://imgur.com/RBemQ1n You usually lose 0.5-1gal of liquid to evaporation, and you need to leave about 0.5-1gal behind for starter for the next batch. You'll be able to harvest 3-4 gallons from your 1F in a 5 gallon crock. That is using the batch method. You can also try continuous, but your results will vary based on a myriad of factors.

Also, consider one of these to keep the temperature consistent, and higher than room temp... otherwise 5 gallons can be a slooow brew:
https://www.amazon.com/Eagle-Brewing-FE650-FermWrap-Heater/dp/B00ODSS3LI

Or make your own:
https://www.reddit.com/r/Kombucha/comments/68z0d1/diy_fermentation_heat_wraps_instructions/

Hope this helps!

For temp control, you want something like This to control your heating/cooling, and a Carboy Wrap to heat your FV up.

If you get a thermowell you can put the temp probe down in your fermentation vessel, rather than just taping it to the side - you'll get more accurate readings. Downside is you can't set up a proper 1" blowoff hose, and counter-intuitively the first few days of fermentation (When you really need a blowoff hose) are the most critical to temp control (Based on what I've read in other threads here)... Might work well if you get a 6.5 gallon carboy, and do 5 gallon batches in it, so you've got extra head space for all the krausen. You can also use some standard size siphon hose as a blowoff, it's just more prone to clogging than 1" hose.