FAQ: Grooming for fish

Note the dates of water changes and filter cleaning, water test results, new fish and plants and any changes you notice. Notes help you spot trends, such as rising nitrates, and find the cause of problems faster.

The basic kit: a siphon, a separate bucket, water conditioner, a glass cleaner or scraper, a net, a thermometer and water tests. A towel and long scissors or tweezers for plants are useful too.

A healthy aquarium smells of damp earth or hardly at all. A bad smell usually comes from overfeeding, rotting plants, an unnoticed dead fish or snail, or a clogged filter. Remove the cause and change part of the water.

Milky cloudiness is often a bacterial bloom in a new tank or after a big change, such as cleaning the filter too hard or overfeeding. It usually clears within a few days, so feed less and do not change all the water.

Usually it is tannins released from driftwood, cones or leaves. They are normally harmless and even suit some fish. If you dislike the colour, water changes and activated carbon in the filter help.

Foam is usually caused by a build-up of proteins and organic matter, for example from overfeeding, or detergent residue on tools. Fine bubbles from strong aeration are normal. Foam that does not clear is a sign to change water and review your maintenance.

Inert gravel usually does not need replacing; regular siphoning is enough. Nutrient plant substrate wears out over a few years, so it is topped up or replaced. If you replace it, do it in sections so you do not remove all the bacteria at once.

Rinse gravel or sand in a bucket a little at a time, stirring and changing the water until it runs clear. No detergent is used. Nutrient or special plant substrates usually should not be rinsed, so follow the instructions on the pack.

Most decorations just need scrubbing with a brush in hot water or tank water. Hard decorations and rocks can be scalded with boiling water. Soap and household chemicals are unsuitable because their residue harms fish.

Scrub rocks well and scald them with hot water; wash plastic decorations in hot water without detergent. Some stones can crack with sudden heat, so do not boil them. If you use a disinfectant, follow the label and rinse very thoroughly.

Take the artificial plants out and scrub them with a soft brush in hot water, especially the leaf bases where algae collect. Use a gentler brush on silk plants so you do not tear the fabric.

Use sharp aquarium scissors to cut off yellowed, damaged or overgrown leaves and stems. Stem plant tops can be replanted, while rhizome and rosette plants are best trimmed from the oldest outer leaves.

The usual tools are long straight and curved aquarium scissors, long tweezers for planting and a spatula for levelling the substrate. Stainless steel tools last longer, especially if you rinse and dry them after use.

Long tweezers make it easy to plant into the substrate and remove leftover food, dead leaves or snails without putting your hand in or stirring up the bottom. They are especially useful in deep, densely planted tanks.

Yes, rotting leaves and plant debris break down and raise ammonia and other substances in the water, which feeds algae. Pinch or cut them off and lift them out with a net or tweezers.

New driftwood often grows a white slimy film that is usually harmless and disappears within a few weeks, and shrimp and snails happily eat it. You can brush it off or siphon it away. Do not clean wood with chemicals.

Many types of wood float at first, so before going into the tank they are soaked in a bucket for days or weeks with changes of water. Meanwhile you can weigh the wood down with a rock or fix it to a stone base.

An air stone gradually clogs with limescale and algae, so the bubbles become uneven and the air pump works harder. You can scrub it, scald it with hot water and blow it through, but often it is simpler to replace it.

Keep the pump above the water level or fit a check valve so water cannot siphon back into it during a power cut. Clean the air intake filter now and then. When the airflow weakens, the diaphragm often needs replacing.

Unplug the heater and let it cool in the water, usually for about half an hour, because hot glass lifted into the air can crack. Wipe off deposits with a soft sponge and never switch a heater on out of water.