Bests & Worsts Reviews from Amazon

See important update at bottom - I bought this tank a my local fish store on a whim and I absolutely love it. I'll talk about the "pros" first and then the "cons". Pros: The sides of each tank are frosted. This prevents the bettas from seeing each other and getting stressed out. I was worried that this might be a huge problem until I noticed the frosted glass. Each tank is actually fairly large - the picture doesn't really do it justice. If I were to guess, they would be about 3/4 gallon. While it is recommended that bettas have at least 2 gallons, my fish seem very happy with their tank setup. They have plenty of room to move around, stretch their fins, and turn without problems. The fact that they have flowing water also helps them to have a bit of current to swim against when they want to, kind of like those "infinite" swimming pools you see advertised on TV. Though, on the waterflow part, read my comment in the "Cons" section. The base holds another couple gallons of water which acts well as a buffer for water chemistry and temperature fluctuations. If you are a good fish parent, you will also add SeaChem's Matrix in a small filter bag to the bottom. Matrix is basically pumice stone and has a massive surface area which allows beneficial bacteria to attach and break down the fish waste. This will help keep the water fresh and reduce scum, bad smells, and algae in the tank. You could also add another small filter bag with activated carbon to keep the water crystal clear. If you keep the temperature relatively low in your house, the base also has room to put a small, 2.5W heater. If you home stays around 70 or higher, this isn't necessary - the tank lids reduce evaporation to keep the water warm and the pump itself generates a small amount of heat. I keep my apartment around 68 degrees and the water measures around 71 degrees without any heater. The tank lids are grated at the water outputs. This prevents your bettas from swimming "downstream" into another tank and getting into trouble. The way the tank is setup, you can also put glass beads/marbles in the bottom and place LED lighting underneath for a really cool effect. From a fish-health standpoint, I wouldn't recommend this as gravel/sand create a biological filter and glass beads do not. And last, but not least, this tank is VERY attractive. The curved shape would allow a betta fanatic to buy ~4 tank systems and place them in a circle...and if I had a larger apartment, this would absolutely happen. Another neat "feature" of this tank is that you could easily place different decorations in each sub-tank to specifically contrast each betta and bring their colors out. Cons: The first complaint I'd have about this tank is that there are no feeding holes on the tank lids. There are the openings where the water falls in, but if you place you food there, the current pulls the pellets underwater and quickly into the gravel where it is hard for the betta to get. As a result, you need to take the lid off each tank to feed the fish when the pump is on. The last lid is a little "tricky" (though not difficult) to get off. The second issue I find with this tank is bettas aren't a huge fan of water flow. They have big, glorious fins that they LOVE to fan out and display. When there is too much current, they won't fan their fins as they get swept away. You can turn down the water pump fairly low, but you still need to get several fake plants (or real if you don't mind the upkeep) to break up the waterflow and give the fish a place to hide/rest. Something I'm doing to help with this I've connected the pump to a timer - I have the pump turn on for 30 minutes to clean up the water and then off for 2.5 hours. The last issue I found with this tank is that the water is not very easy to change. The only way to change the water is turn off the pump and then siphon it off from the base with a small tube. Update - April 28th, 2014 The tank lids with the grating on them to prevent bettas from going in between the tanks have ~1/8 inch gap between the tank and the beginning of the grating. As a result, bettas can squeeze through. One of the things that bettas are famous for is sleeping up against outflow grates and one of my younger veil tails managed to wiggle through. I'm very lucky that I was home to notice this and get him back into the right tank (otherwise, I would have a dead betta and another very beaten one). Until Aqueon fixes this (and they probably will), you need to pick up something to squeeze into the 1/8" gap. I'm using a sprig of anacharis to plug each gap, though a bit of fake plant, filter material, or blue bacteria sponge would work too.