Additional equipment for aquarium maintenance.
The main requirement for items needed to maintain an aquarium is that they must be made of materials that do not release toxic substances into the water. When moving equipment from one aquarium to another, it should be thoroughly disinfected. For example, if pathogenic bacteria have settled in one of the aquariums, an item transferred from that aquarium can become a carrier of the disease.
• Quarantine aquarium. This is a small additional acrylic aquarium used when one or more fish need to be kept in isolation — for example, during treatment and quarantine. However, it must have a lid or cover glass, as well as its own water heating and aeration system. A filter may also be required, depending on the circumstances. Usually, a sponge filter is used.
• Aquarium divider. Used to divide the aquarium into separate sections — for example, to isolate aggressive fish from each other, ensure peace and quiet for a sick fish, or provide privacy for spawning fish. A divider is usually a temporary measure used while waiting for a more permanent solution to the problem. You can buy ready-made dividers or use sheets of glass or transparent plastic of suitable sizes.
• Fish feeders for artificial, live, and dry food differ in their design and the materials from which they are made. 
These are glass, plastic, or styrofoam feeders without their own mounting hardware. Using a suction cup, they can be attached to the glass. Feeders for dry and frozen live food have started going out of style and are no longer used because it is inconvenient for all fish to crowd around a 5×5 cm feeder. It is better to throw all the food on the water surface, and the fish will gather it themselves; the same happens when feeding with frozen food. Food storage boxes and frozen food containers can also be used.
• Fish nets are used for feeding fish, catching fish, and catching and sifting food. A small net (4-6 cm) is used for feeding fish. Food organisms are placed in the bag, rinsed with water, and fed to the fish. The frame of the net for catching fish should be rectangular in shape so that the net can easily penetrate the corners of the aquarium where frightened fish most often hide. The net is made of nylon mesh. Fish that flare their spines at the sight of danger (e.g., catfish) require special nets made of dense fabric because they can get tangled in ordinary nets. The sizes of the nets are determined by the size of the fish and the capacity of the aquarium. The size for medium fish is 6×9 cm, and for large fish 10×15 cm.
• Buckets are necessary for various purposes. Standard plastic buckets are not made of food-grade plastic, but they can be used to remove dirty water. For water poured into the aquarium, it is better to use enameled buckets.
• Gravel vacuum (siphon). Used as a “vacuum cleaner” for the substrate. It removes detritus well. It is also useful for draining excessively silted substrate. However, it should not be used for this purpose 
during regular weekly aquarium maintenance, as this will deal too heavy a blow to the population of beneficial microorganisms living in the substrate and biofilter.
• A hose is necessary for water changes and cleaning the bottom of the aquarium from accumulated dirt. Any hose made of flexible plastic can be used for this. It should have a diameter of 8-12 mm and a length of 1.5-2 m, or even better, long enough to reach the bathtub or toilet.
• Glass cleaners (magnetic and regular scrapers, brushes) are used to clean the viewing glass from algae. Magnetic glass cleaners are available for sale, consisting of two parts: the outer one, which moves outside along the aquarium glass, and the inner one, which moves inside, following opposite and wiping away the algae coating. In silicate glass aquariums, you can use a glass cleaner consisting of a holder with a safety razor blade fixed in it and a long handle. When using scrapers with metal blades, care must be taken because they can scratch the surface of acrylic glass or cut the silicone sealant in the corners of the aquarium. It is safer to use scrapers with plastic blades. To avoid scratches on the glass, it is better to insert a sponge or hard rubber plate instead of a razor blade.
• Tweezers for planting and feeding fish. Scissors for trimming leaves and plants.
• Water conditioning products include a whole range of items — for example, dechlorinators, copper removers, and other toxic substance neutralizers; mineral salts, pH adjustment agents; plant fertilizers; tonics, etc. Some of them are truly useful and necessary, while others can be replaced by mechanical filtration or natural methods. It is very important to understand that the possibility of chemical water treatment does not at all mean that it is truly necessary in every case.
Too many aquarists believe (or are led to believe) that their fish cannot survive or stay healthy without the use of such water treatments. However, we must remember that fish lived and reproduced in aquariums long before most of these substances were invented. If you expose fish to a mixture of chemicals, it can be extremely harmful to them. If water treatment is still necessary, choose the required chemicals made by the same manufacturer. As a rule, they are formulated so that their combined use is safe (unless otherwise specified in the instructions). Using products from different manufacturers can lead to undesirable chemical reactions and fish poisoning.
• Medications. It is necessary to have a basic set of medicines for treating common diseases of aquarium fish. Syringes for measuring medicine dosages. A container for diluting medicines.
• Test kits for determining water quality parameters and chemical composition. Tests from different manufacturers may use different analytical methods. Often, a test is a kit consisting of several bottles of chemical reagents and a measuring container for the water being tested. Reagents can be not only in liquid form but also in tablets, powder, or test strips dipped into the water sample. Most kits also include a reference color chart. By comparing the colors of the test strip or sample with the chart, test results are obtained. Pay attention to the expiration date of the test kit as well.
• Thermometer for measuring water temperature. It can be inserted into a suction cup holder and attached to the aquarium wall.
• A small amount of gravel, sand, and small stones for planting plants in pots and substrate.
• Sponges and other filter media for replacement in filters.
• Zeolite, granulated peat, and activated carbon for use when necessary.
• Spare shelters for fish that need them.
• A spare, inexpensive aerator and heater for temporary use in case the main ones break down.
• Silicone sealant has many uses — for repairs, sealing, etc. In addition, it allows you to craft some equipment yourself. Use only sealants specifically designed for aquariums. Construction silicone sealants may contain toxic fungicides and colorants.
• Magnifying glass with three to five times magnification.
• Spawning aquarium. This is a small additional acrylic aquarium used when one or more fish need to be kept in isolation during spawning. However, it must have a lid or cover glass, as well as its own water heating and aeration system.
• Special equipment for culturing Artemia, infusoria, and other food for fry and fish.
• Nets to protect eggs during fish spawning.
• Breeding boxes for livebearing and killifish reproduction. Breeding boxes are used in the main aquarium if it is necessary to isolate fry and fish from more aggressive or larger neighbors. Breeding boxes are attached to one of the aquarium walls using brackets or suction cups. Breeding boxes for incompatible fish species are also available, partitioned with a divider.
• Jars and thermos flasks for transporting fish.
Ultraviolet lamps — what are they needed for in aquarium hobby.
Basic aquarium maintenance procedures. 
