Your Aquarium FAQs Answered

Home aquariums require a lot of care and attention, but we don’t expect all fish tank owners to be completely versed in the complexities of tank maintenance. To help fellow aquarium enthusiasts, we’ve put together a list of the most frequently asked questions and their answers. Whether you’re an experienced aquarium owner or a beginner, these questions can help guide you through the process of keeping your fish happy and healthy.

How Often Should I Change the Water in My Tank and/or Clean My Tank?

Partial water changes of 20-30% should be occurring every two to three weeks. So that fresh water is consistently being added to the tank. Similarly, cleaning should occur in increments on a regular basis. You can remove uneaten food and top up water levels as required on a daily basis. Cleaning the inside glass of the fish tank with a magnet cleaner can be done regularly to prevent build up of algae and keep the tank looking good.

More general, large-scale cleanings should occur fortnightly or monthly. This includes a gravel vacuum and filter clean. Use a gravel vacuum to siphon out fish waste and debris from the substrate. Keep a bucket of water aside from the water change and give your aquarium filter media a quick rinse in this bucket of water. This will prevent killing the good bacteria in your filter. This will remove trapped waste and allow your filters to work more effectively.

Avoid using tap water to clean your filter media as this will kill the good bacteria living in the filter media, causing your tank to go milky or cloudy a few days after your filter clean. Replace old or clogged up filter media as required. Water tests to monitor the water quality should happen monthly. Also remember to clean the glass lids, air pump tubing, the filter hoses and pipes, and the filter intake periodically as needed.

What Filter System Does My Aquarium Need?

These days a lot of aquariums come with filters built into the tank or come with a filter included in the package. If your aquarium doesn’t come with a filter and you would like to choose the correct water filter system, there are a few types of filter options to choose from.

1. Air-operated filters: As the name suggests, these filters use air from an air pump to draw water through a sponge. Sponge filters are the most basic, effective and economical options for filtering water in a fish tank. They are perfect for small tanks, quarantine tanks and shrimp tanks.

2. Internal Filters: Internal filters are great value for money and very easy to use. The filter is completely submerged in the aquarium and uses a powerhead to draw water through the filter media.

3. Hang-on filter: Sometimes known as hang-on back filters, they are designed to be clipped onto the back of your aquarium. These filters are very effective as they use a range of filter media to filter the water.

4. Canister filters: Canister filters are considered the best aquarium filters for your aquarium. This is due to the large volume of mechanical, chemical and biological filter media you can fit into a canister filter. The filter media inside can also be easily changed and customised to suit your needs.

How Many Fish Can I Have in My Tank?

Your pet store should be able to advise you on the appropriate amount of fish for your tank when selecting them, but the general rule is to have a maximum of 2.5cm of fish per 4L of water. Use this as a rough guide but fish come in many different sizes. The number of fish will depend on the size of your tank and if your aquarium filter can handle the amount of waste produced by the fish.

When deciding on the amount of fish you want, be sure to consider the breed of the fish and the amount of water that will be left inside the tank after you’ve added gravel and decorative features. It’s incredibly important not to overload your tank and allow enough space for them to grow.

How Often Should I Feed My Fish? What Should I Feed Them?

Consistently overfeeding your fish can lead to health problems such as bloating and indigestion, as well as issues with the water quality of the tank. To avoid overfeeding, feed your fish small amounts 2–3 times a day rather than one big feed every day. Pay attention to how much food is left in the tank 5 minutes after feeding your fish and adjust their portions accordingly. Fish shouldn’t be given any more food than they consume in a 2–3 minute period.

What you should be feeding your fish will depend on the type and size of the fish and what they would normally eat in the wild. Today, there is a large range of commercially available fish foods to suit most fish. These come in a variety of sizes, so choose one that your fish can comfortably swallow or nibble at. For smaller fish we generally recommend a flake food or smaller granules. For medium and larger sized fish we use a mix of floating or sinking pellets and granules.

Some fish are carnivorous meaning they prefer a meat-based diet. These include food which have higher quantities of bloodworms, insects, shrimp or fish. Some fish are herbivores and like to graze on algae, feed them foods with higher algae and spirulina content.

What Are Good Fish for Beginners?

If you are new to the aquarium hobby, it’s a good idea to get hardy, tolerant fish who can handle some inconsistencies in water temperatures and quality. For a community tropical tank, swordtails, platies, guppies and mollies make excellent beginner fish for that exact reason. Many species of tetra, corydoras and rasboras are also easy to care for.

For a coldwater tank the common goldfish, comets and koi are very hardy and easy to look after. It is recommended that you start with just a small amount of relatively self-sufficient fish while you get the hang of things.

What Temperature Should My Water Be?

The temperature of the aquarium will depend on the type of fish you are keeping. For cold water fish like goldfish you can keep the temperature from 15–24°C. To accommodate the majority of tropical fish species, the water in your tank should sit between 24–26°C. However, some species of fish, like discus, prefer higher temperatures between 28–31°C.

Do I Need to Put Plants in My Fish Tank?

Aquarium plants will be highly beneficial to your fish tank, as they boost oxygen levels and combat excess algae growth. They do, however, require a little extra work on your behalf, as they need fertiliser and a certain amount of light to survive. While they are visually and practically an excellent addition to your tank, they may get nibbled on by some fish. This is something to be aware of when choosing your aquarium plants and fish.

Why Does the Water in My Fish Tank Look Green or Cloudy?

When an aquarium is first set up, it will experience a bacterial bloom that will turn the tank green or cloudy. This cloudiness is completely normal and should disappear within the following days or couple of weeks. If you want to speed this process up, you can complete a 10–15% partial water change and vacuum the gravel about a week after setting up.

Green and cloudy water can also be caused by too much light, either from the sunlight hitting the tank or from aquarium lights being left on all day and night. Limit the amount of light exposure to around 8 hours per day and use an algae killer to inhibit further algae growth. Algae eaters like snails, sucking catfish or bristlenose and plecos can be added to help reduce algae in aquariums.

Where Can I Find More Advice and Information?

The enthusiastic team at Aquarium Kingdom are experts in maintaining tanks and caring for fish. Whether you have basic, beginner-friendly questions or niche and complex queries, we are always happy to guide you through the exciting world of home aquarium ownership. Browse our online store today for the best fish tank tools and features on the market, as well as a range of high-quality fish foods.