So this weekend I'm taking the plunge and setting up my divided tank. I wanted to do this cheaply. Having just set up TWO more tanks thanks to the Petsmart "oopsie" Fluval V sale, I need to minimize maintenance because I now have 5 tanks at my house and one at work. Going to put my 2 guys from their 10 gallons into the 20 long - with *maybe* a third section for another fish. I'd do the sections 7.5 gallons, 5 gallons, 7.5 gallons because I feel bad about downgrading my existing guys from 10 whole gallons to themselves. Both tanks are cycled, and I figure it probably won't put too much of a strain on the system to add one more fish for 2 established filters to handle together. Will keep an eye on the water parameters if I do add a 3rd.
$20 for tank via Petco $1/gallon sale
$8 for an undercabinet T8 fluorescent fixture from Wal-mart
$5 corrugated plastic for divider
$4 can of black krylon fusion spray paint
$12 glass versa top
$0 scavenged/leftovers from other tanks/cannibalizing from existing 10 gallons: filters, heaters, substrate, plants, fish, snails, vinyl rain gutter for light fixture housing, computer cooling fan for light fixture (if needed)
Feeling of accomplishing a cheap upgrade which will reduce maintenance: Priceless
I will keep the 10 gallon tanks in case the dividers don't work out for one of the bettas. They are both very mellow and already have their tanks literally right next to each other. They see each other all the time. I also have two others to play musical bettas with if anyone can't stand sharing a tank.