Home Aquarium Fish

OK, you’ve acquired your first fish tank and now you want to know what home aquarium fish to buy?

The first thing is – don’t go at the job too quickly, patience is a virtue in fishkeeping!  You see fish, like any other creature, excrete waste products.  If they are doing that in the vast expanse of a lake or river or even the sea, then it’s so diluted it doesn’t really matter.  But in the confines of the home aquarium fish producing urine and faeces can be bad news, as the waste products can get over-concentrated and poison the fish.

The good news on the flip side of this is that if you have a filter in the tank, which is a must, beneficial bacteria will grow on the filtration medium, whether it’s sponge, gravel or a specialist medium, and these bacteria will consume the ammonia excreted by the fish and convert it into nitrites and thence into more benign compounds such as nitrate. 

The thing is, unless you use artificial means of “maturing” the filter’s bacteria, you should add your fish just a few at a time, over a period of weeks.  This is because it is a gradual process that enough bacteria develop to deal with the amount of waste produced at one time.  Then you add a few more fish, and this way you never end up with the crisis that ensues if too many fish are producing too much waste for the bacteria to cope with.  This is known in the trade as “new tank syndrome” and it is why so many budding fish keepers lose fish and are disheartened with their first experience of fishkeeping.

So, a few home aquarium fish at a time – or if you go into the subject in more detail, you can mature the tank water before adding any fish at all – but both methods take patience. 

But what type of home aquarium fish to choose?  Well, broadly speaking, in general terms of skill level, expense and complication, there are three broad types of home aquarium fish you could go for:

Coldwater fish (goldfish etc)

Tropical Fish

Marine (Saltwater) Tropical Fish.

The cheapest option to buy is coldwater – although there are some fairly expensive fancy goldfish and koi out there, they are generally suitable for the home aquarium fish enthusiast and the pond (or huge tank) keeper.  They need filtration and regular partial water changes because they produce amazing amounts of solid faeces, usually in long and fascinatingly ugly strings!  However they don’t need a heater so in that way they are cheaper.

Freshwater tropicals are the most popular choice of fish, even though they require heating and filtration in the tank.  There is a huge choice of tropical fish of many different types, and they actually can be less trouble than coldwater in that they are not quite so “mucky”.  Good tank maintenance on a regular basis is still necessary.

Marine tropicals are considered the crème de la crème of the home aquarium fish market.  They are often wildly colourful, expensive and delicate.  These should be left to the more experienced fish keeper as the maintenance of good artificial seawater (it contains a lot more than the salt you put on your potato chips!) is quite a complex subject.  Without it these expensive and beautiful fish would die.  It is certainly within the reach of the home aquarium fish keeper, and marine tanks are popular the world over, but it is best to graduate to marines after serving an apprenticeship with freshwater tropicals.