free delivery over £120

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Orders under £20 are subject to a £5 surcharge*

free delivery over £120

Orders under £20 are subject to a £5 surcharge*


dwarf cichilds
gourami paradise fish
l number plecos
rainbow fish

Tropical Fish 

Delta Aquarium specialises in high quality tropical fish for sale in the UK – Delivered Safely to your door by us. 

From your bread and butter fish to your oddball fish, you can find it here. We have an ever-growing selection of tropical fish, inverts and amphibians with new species arriving every week. If you cannot find what you are looking for, please ask a team member and we can source the tropical fish for you.  

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Tropical Fish FAQS

Is it OK to buy tropical fish online?

Yes fish are absolutely fine to be shipped, fish stores have their fish shipped to them also so it doesnt make a difference whether buying online or at a store. Your fish will have been shipped at some point. We want our quality livestock to be delivered in the best condition. We use high-quality poly boxes and heat packs. We ensure the bags are filled with pure oxygen and double bagged. We also use a reliable 24-hour licensed courier.

Information I need to know about keeping tropical fish?

If you are thinking of keeping tropical fish, you need to know about the following main things:

Size of your aquarium
Firstly decide how much space you have for your new fish tank. Always go as big as you can fit, the bigger the better with fish keeping.

Deciding what to fish to keep
This will depend on the size of your aquarium. Research how big a fish is and will grow too.  Small-community to medium-sized community set-ups are best to start with unless you’re looking to create a biotope or species tank.

Cycling your aquarium
This is a very important part of keeping your cold water or tropical aquarium. Your filter is just a sponge and is no different than your washing-up sponge…until it’s “cycled” and loaded with beneficial bacteria.

Maintaining your aquarium
You should clean your tank on a weekly basis. A small 10-20% water change will help remove any build-up of waste. Siphon your substrate and clean the glass, this will keep your tank nice and clean for your fish.


Tropical Fish for sale, contact Delta Aquarium UK here if you need any advice please give us a call!

Do tropical fish need a heater?

Yes, tropical fish will require a heater. A heater ensures the temperature stays steady during the course of the day. Generally, 25°C is the optimum temperature to keep most tropical fish, this is similar to what they are used to in their natural habitat.

Can I immediately add tropical fish to a new aquarium?

This is not the ideal or most humane approach, water chemistry is by far the most common reason for fish deaths. To make sure the tank water is safe for them, it’s crucial to buy a test kit and check your ammonia and nitrite levels. Reading up on filtration and the nitrogen cycle is advisable. A new aquarium is basically a sterile, environment when it is first put up. Fish waste cannot be immediately broken down using a new filter. Before it functions well, there needs to be a large colony of nitrifying bacteria present. You don’t want the potentially dangerous chemistry of the water to be harmful to your new fish. When the filter is fully developed, you are able to begin stocking your aquarium.

What other equipment do you advise for keeping tropical fish?

The equipment you will need when it comes to caring for tropical fish include:

A suitable fish tank

Aquarium lighting

Substrates and aquarium plants to help create a healthy ecosystem

A filter system to keep your water clean and clear

An aquarium heater

A thermometer to keep to check the temperature stable

Aquarium test kits to check pH, ammonia, nitrite and nitrate levels

Cleaning tools

How often should I feed my tropical fish?

Most tropical fish generally thrive on one or two feedings per day. You’ll need to adjust the quantity of food according to the size and quantity of fish in your tank. If your aquarium is new and you have just added your first fish, feed every other day and count the amount of food you are adding. A “pinch” is not accurate enough and may lead to overfeeding your fish.

Looking for high-quality Tropical Fish for sale in the UK, Delta Aquarium has you covered, if you need any advice please give us a call!


How many tropical fish am I allowed to keep in my aquarium?

The typical rule of thumb is one inch of fish to one gallon of water, another wise rule is: If your aquarium appears overcrowded, it usually is! But the amount also depends on the tank’s filtration system. More fish waste will be effectively broken down by a large external filter than by a small internal canister filter. Monitoring your aquarium’s ammonia and nitrite levels could help you determine if there are too many fish in there for your filter to cope with. A few hours after feeding, if you notice rises in these chemicals, it means your filter is not coping effectively.

If you are looking for top quality Tropical Fish for sale in the UK, Delta Aquarium has you covered, if you need any advice please give us a call!

Are live plants necessary in a tropical fish tank?

Live plants provide benefits such as oxygen production, nutrient absorption, and a natural environment for fish. While not mandatory, they contribute to the overall well-being of the aquarium ecosystem.

Quality Tropical Fish for sale in the UK,  if you need any advice please give us a call!