Join Date: Mar 2019
Location: Gresham, OR, USA
I've got a Spec V that's housed two reasonably long-tailed bettas (not at the same time, obviously). I cut about 6 notches in the hose leading from the pump back into the tank to slow down the flow a bit and provide more water circulation for the heater I've got in the pump chamber and I aim the outflow nozzle up. It's got good circulation and the bettas get around fine. Both of them spend a good bit of time chilling against the filter intake or in the plants, but they did that even when I had a sponge on the filter outflow that really cut down on water circulation. When I had a sponge on, I got horrendous algae issues due to lack of circulation and I suspect I'd have had water quality issues if I had more than a single betta in there and I hadn't taken the sponge off the next day (other people use the sponge with no issues, so I don't know what was different about my tank - even with the pump on its highest setting, I couldn't get enough flow with the sponge on). Sometimes my current betta will go swimming wildly after some food and get buffeted about a bit by the current (he normally avoids the area with the strongest current or swims calmly through it). He's fine, though - I just tell him his butt is too pretty for such shenanigans.
I really like the look of the tank and highly recommend getting a heater that fits in the pump chamber to keep the clean look. The lack of front-to-back distance is quite limiting for aquascaping, but if you're prepared to work with it, I think you can get some really nice setups, and I love the length of the tank.
I only use the light it came with and I've got plants coming out my ears (mini dwarf hairgrass and cryptocoryne undulata "red" mostly - the crypt isn't the reddest of red plants I've seen, but it's decently red for a non-plant-specialized light).
Oh, and the filter/pump is *suuuuuuper* quiet - I have pretty significant noise issues and I can sleep with it in my bedroom. When I had it in my kitchen, if you were standing right next to the tank, the refrigerator across the room was louder than the tank!