Which community fish should I choose?
Please could you offer me some advice on setting up a 90x38x38cm tropical community tank? I’ve been keeping aquaria for some time, but this is my first community tank and I’m unsure about the right fish to choose. I’m searching for hardy, easy-to-keep fish that can tolerate fluctuating pH, KH and GH—basically, general West Yorkshire tapwater. I’ve set my heater to 75°F.
With regards to bottom dwellers, I wish to keep a shoal of Corydoras— albino, bronze or peppered – and perhaps some Kuhli loaches. I’d also like some Otocinclus and perhaps some shrimps as well. But I’m unsure about fish for the upper levels of the tank. Please could you advise?
BOB SAYS: You’re doing the right thing in researching potential fish choices before adding them. At around 120 litres before displacement for décor, substrate and suchlike, your tank is a good size, and this helps widen the range of suitable fish. You mention the fluctuating chemistry of your tapwater, but it’s still worth checking what the parameters in your tank are before deciding on fish, to make sure they’re the best fit for it.
All the fish you mention are bottomdwelling species that need to be kept in groups of five or more and if you added all of them, the lower levels of the tank would be rather crowded.
The three species of Corydoras you mention are actually only two: bronze and albino are both C. aeneus, and you can mix the two colour-forms without problems. Either these or the peppered corys, C. paleatus are a good first choice, being among the hardiest available, although C. aeneus are a little more resilient. A group of at least five
Corydoras would be ideal.
Kuhli loaches, Pangio sp. are wonderful little fish, but not as hardy as the corys, preferring softer, more acidic water, and they can be very secretive unless kept in large numbers.
Otocinclus will nibble at algae on the glass or décor, but they are best added to mature tanks and seldom thrive in new set-ups.
Shrimps make fascinating aquarium subjects but can be more sensitive to poor water quality than many fish. Similarly, many medications for diseases and parasites cannot be used with them present, so I would delay adding any until your tank is more mature and you’re more confident in the care of your new pets.
Obvious choices to add colour and movement to the upper layers are popular tetra species like glowlights and X-ray tetras, or less feisty barbs like cherries. Livebearers, such as platies, are also great, colourful choices but you can become quickly overrun with fry, so I’d recommend only stocking male fish—a good shop should be able sex them for you if you’re not confident yourself. Like the bottom-dwellers, these are all fish best kept in groups of five or more of their own kind.