Fish Care

A dither fish is an active, visible fish you add high in the tank to tell the nervous fish below that no predator is about, so they stop hiding and start behaving normally. That is the whole idea. In a cichlid tank it does a second job too, giving a bully something to chase that is fast enough not to get hurt, which takes the heat off the other cichlids. Whether you actually need one depends entirely on which cichlids you keep, and in my experience plenty of hard-water setups do fine without any. I have run shell-dweller colonies for years with nothing swimming above them, and run others with a shoal up top that changed the whole character of the tank. Here is how to tell which situation you are in. ...

The short answer is that you can, but most of the time you should not, and the reason has nothing to do with water. People ask me this all the time because both lakes give you hard, alkaline, colourful African cichlids, and it seems obvious they should share a tank. The water chemistry really does line up. Everything else pulls them apart. I have kept both lakes, in separate tanks, for years, and this is the honest version of why that separation exists. ...

The best pH for a betta is around 6.5 to 7.5, close to neutral. That said, a betta cares far more about a stable pH than a perfect one, and chasing an exact figure with chemicals does more harm than the reading you are trying to fix. Bettas are farmed by the million across a wide range of water and adapt to most steady conditions, including hard, alkaline tap like mine. ...

Neocaridina cherry shrimp do not need a heater in a normally heated room, because they are comfortable anywhere from about 18 to 26 degrees Celsius. If your room sits reliably in the high teens or low twenties, an unheated shrimp tank is fine, and I run several of mine that way. A heater becomes worth adding only when the room gets genuinely cold or swings sharply between day and night. ...

Of all the clean-up animals I have kept, the nerite snail is the one I recommend without hesitation, and it happens to be a perfect match for hard tap water. Most freshwater snails simply tolerate the minerals in hard water; the nerite depends on them. Those minerals are what keeps its shell hard and smooth, so the very water that troubles soft-water fish keepers is a gift to nerite keepers. If you have algae on your glass and hard water in your tap, this little snail is about as close to a purpose-built solution as the hobby offers. ...

If your tap water is hard and alkaline, and a lot of ours is, the molly is close to the ideal fish. Most of the popular community species were bred for softer, more acidic water and only tolerate what comes out of my tap; the molly actively wants it. Warm, mineral-rich, slightly alkaline water is exactly the environment these fish evolved in, so for once the water that fights you with tetras and rasboras is working in your favour. Here is how I keep mine, and where people go wrong with them. ...

Quarantine is the least glamorous subject in fishkeeping and the one with the best return on effort. Nobody sets up a quarantine tank because it is fun. You set one up after the first time a bag of new fish brings ich into a display tank you have run cleanly for two years, and you spend three weeks treating every fish you own because of six new tetras. Most keepers learn it that way. You can learn it the cheap way instead, which is what this article is for. ...

Nobody has ever brought me a tank problem that turned out to be underfeeding. Not once. Skinny fish in home aquaria are almost always sick or bullied, not starved. Meanwhile overfeeding sits behind most of the cloudy water, algae outbreaks, snail explosions and mystery ammonia readings I get asked about. Fish are small, cold blooded animals that spend most of the day doing very little. They need far less food than our mammal instincts tell us, and the kindest thing you can do for a tank is to feed it less than feels right. ...