A biotope is a way of trying to recreate the natural environment your fish originally evolved from. Even if your fish has been breed in tanks for generations they all seem to improve if given their natural environment back. These can look stunning, and be a real talking point, who needs a feature wall when you've got a feature tank. So what sort of ideas are there. Well as many as there are natural environments, you can recreate a river from Asia, or a slow moving stream from the Amazon, maybe a paddy field or a brackish river, or a rift lake tank. The advantages to the fish are clear, the best water that they require, tank mates that are also suited to those conditions, that's not to say you can have any fish from that environment, there are still unsuitable combos, but there will be a lot of suitable candidates. There are purists out there that do their research properly, and create a miniature aquascape, exactly like it is in the wild. I have to own up, I take the slightly less stringent route. I aim to create something that looks approximately correct. For example I tend not to mess with my water commentary, the reason being that stable water is better than water that might fluctuate. Plus I've had a run of killing plants, so anything technical is out for a while. But it should provide everything your fish needs, hiding places, or areas to swim, the correct water parameters and enough space. So let's look at an example or three, feel free to get things exact, but for me it's going to be a bit more relaxed. Also since I have a budget to stick to I have to sacrifice being exact for affordable. Probably one of my favourite biotopes is anything to do with the Amazon. Having studied fish out there the sight of this little slice of nature in my living room takes me back. The Amazon is a huge river system, but for my latest project I built the system around my angelfish. The first consideration is where they've come from, the most commonly kept angelfish P. Scalare comes from the Amazon basin, commonly found around flooded vegetation in water between 24 and 30 degrees, around pH 7. They are ambush predators, and will eat anything small enough to get in their mouths. Being a tall fish they need an aquarium with some depth, luckily I was building this biotope in a 4 foot long 2 foot high tank which gives them plenty of depth. My water is normally around pH 7, which is perfect for the angels, and partly why I chose this species. The next choice was tank mates for my group of five angels. Since they will snack on anything small enough I went for a larger species of tetra, or at least I will once I've found the ideal species, maybe Roberts' tetra. Plants have been my Achilles heel for a while, for this I chose Amazon swords and they have been proven to be tough enough to withstand my poor plant keeping, I've also cheated and put a few plastic plants amongst the real, I can't manage to kill them. My next tank is for in the bathroom, something to look at whilst you're relaxing in the bath. For this I decided to replicate a paddy field biotype, with the focus on the plants, rather than the fish. I've planted black rice that will grow with their roots into he water and the stems coming out into the air so I don't have to inject CO2. The tank here is quite small, it's a cylindrical tank two foot tall, but only 18" wide. Meaning it is less than 100 litres in total, so I don't want to over load it with fish. The star of the show will be a Betta splendens, those wonderfully showy fish known as a Siamese fighting fish. Since the tank will be heavily planted I may source a nice group of females to keep him company, or he may live in regal splendour on his own. My final tank idea is an Asian river tank. I have a six foot by 1 foot by one foot tank that is just sitting there doing nothing. So I will be hooking up a big power head at one end, with the intake at the other end. Decorating it with plenty of stones and gravel and a huge branch. Maybe manage to get some plants to grow out of the water if the flow isn't too high. Fish species will be a big school of White Cloud Mountain Minnows, some of those poor hill stream loaches that are so often sold as suitable for tropical tanks, maybe 10 of those and even some barbs that are suitable. Because of the high flow, and the fact that the tank isn't very tall I'm doing away with having a large fish as the centre piece, but might get some form of bottom feeding loach. One thing to remember is that the bulk of fish available in the aquarium trade have been bred for generations in tanks and have adjusted to those parameters. If you are going to change things do it gradually, your fish will prefer it. The main problem with all the above tanks is simple. I've run out of room in the house. I'm having to wonder is it too much to move house so I can set up some more tanks.