In aquascape, everything should look and behave as naturally as possible, therefore you should avoid unnatural-looking decorations such as skull, treasure crate, colorful marbles/gravel, plastic divers, castles, shipwrecks, plastic plants, etc. All of the unnatural aquarium ornaments make your aquarium looks like a 'toy-aquarium'!, but some artificial fish decorations can be useful for some reasons - we'll discuss about it later.

Natural woods and rocks are commonly used for aquascape, but be careful, you shouldn't use any materials that you find yourself, it could rot or may contain harmful substances. Some other considerations are as follows:

Aquarium Wood

Aquarium plants for fish decorations are not enough, we should add some woods, roots and rocks to optimize the aquascape appearance. Besides, as fish decorations, woods are useful for:

• Hiding places for your fishes. By providing your fishes with the shelter they need to feel safe, you'll reduce the fishes' stress.

• Covering in-tank equipments such as heater, internal filter, filter's intake or airstones as much as possible.

• Anchoring media for some aquarium plants such as Microsorium pteropus, Anubias or Java Moss. They are at first held in position with thin threads.

Microsorium pteropus (Java Fern) on a bogwood Anubias barteri var nana on a bogwood Java Moss

Aquarium driftwood, savannah wood and mangrove wood are usually sold at the aquarium stores. Whatever choice you made, the wood should be free from lime, sink and already seasoned to avoid from rotting. I disagree with the advice to weigh down the floating wood with some rocks. Before you use it as an aquarium ornament, you should soak the wood for maximum a week, if it's still float, it can't be used.

Almost all natural woods secrete tannins. Tannin is an acidic substance that makes your aquarium water brownish and can lower the pH. In Amazon-river biotopes, the pH are below 7 (weak-acid) and have brownish water due to tannins from tree roots all along the river.

Tannin from an original aquarium wood can NOT be cured by boiling it for hours, the wood will keep secreting tannin for years until the tannin entirely used up. Regular water change can only reduce the brownish water temporarily, while using active carbon (to remove the tannin) in filtrations will also remove soluble nutrients that needed by aquarium plants!

Genuine aquarium wood is not only a beautiful and a natural addition to a freshwater aquarium, but it's essential for keeping a "blackwater" rainforest tank (where tannins would be naturally present) and for some wood-eater fishes, such as panaque and other suckermouth catfish which need a large amount of wood fibre for their properly digestion functions.

Some hobbyists don't like the brownish water - even when they keep Amazon's fishes such as discus, angelfish, tetras (i.e. neon, cardinal, red-nose, x-ray tetras), etc. If you want a crystal clear water and need realistic aquarium ornaments, a fake aquarium wood is the answer! The artificial aquarium wood can give you an authentic, natural look without worrying about tannins, and epiphyte plants can also stick to it - no difference with the real aquarium wood.

Aquarium Rocks & Caves

Rocks are natural aquarium ornaments for fish decorations. They add esthetics in aquascape, also can be used for some aquarium plants' growing-media and to cover in-tank equipments. Many rocks can be used for aquarium ornaments such as river stones (black), lava rocks (red), etc. Whatever kinds of rocks that you choose, strictly avoid rocks that containing lime however beautiful they are.

Caves are important for hiding places, especially if you keep aquarium shrimps or crayfish. Natural rocks which have the shape of caves are quite difficult to find, if you really need it, check out the artificial cave and choose the most natural one for your aquascape.

Rocks should be washed and scrubbed with brush thoroughly under a running water before you use it.

Aquarium Background .

For me, an aquarium background that stick to the aquarium rear-glass is not natural. It is usually used in a smaller tank to create the illusion of more space, but it also can hide hoses, cables and other equipments behind the tank. So, it's up to you to decide, at least choose the aquarium background which resembles your aquascape's theme.

It's important to remember that your fish decorations and aquarium ornaments should be non-toxic! Don't just buy any cheap aquarium ornaments that may leak any harmful substances into the water.

See you in our next articles.