Welcome to the Rock 'N' Critters blog!

This is where you'll find all of our latest updates, as well as insights from our marine aquarium experts. If there's a topic you'd like to see us cover in a future blog post, please feel free to get in touch!

Introducing a coral colony to your marine aquarium is a fantastic way to add a colourful new dimension to the tank. Many fish have a symbiotic relationship with coral, so incorporating a colony into your marine ecosystem may benefit the other inhabitants of your aquarium as well!


Watching a small piece of coral grow into a large colony is one of the most enjoyable parts of managing your very own reef.

Coral fragments can be cut from an existing colony using a pair of coral cutters, but if you'd prefer not to do this yourself, you'll be pleased to learn that we sell a colourful range of coral frags here at Rock 'N' Critters!

Choose from LPS, SPS and soft coral frags.



There are thousands of different coral species on planet Earth, but broadly speaking, they can be sorted into three different categories:

Read on to learn about the differences between these three coral types.


Boy holding his nose because of a bad smell

Does your fish tank smell? If so, there are several possible reasons why. In general, marine fish tanks should be odour-free, except perhaps the smell of the ocean, so if you find that you can smell an unusual or unpleasant odour coming from your tank then you may have a problem that needs sorting out quickly.


Cloudy water in marine aquarium

Ensuring that your saltwater tank is filled with clean and clear water is really important if you want your marine life to thrive. If you wake up one morning and notice that your marine tank has become cloudy, you should troubleshoot the problem and seek a solution right away.

Cloudy fish tank water can be caused by various different things including:

  • Sand being moved around the tank
  • Algae or bacterial bloom
  • Microbubbles in the tank


Common clownfish

So, you want to set up a marine tank? It's an exciting prospect and we're sure you're keen to dive right in and purchase your first fish. But before you do, we advise that you take the time to learn what the best saltwater starter fish species are for your tank.

Keeping saltwater fish is an incredibly interesting hobby and we're sure you'll be amazed by the graceful nature of marine life. But it's easy to get ahead of yourself and choose species that look good but aren't necessarily the easiest to look after.


How many marine fish in an aquarium?

If you've gone to the trouble of buying all the right equipment and setting up your very own saltwater aquarium, you're probably keen to adopt lots and lots of fish. Most marine aquatics enthusiasts want their tanks to be as lively and as colourful as possible!

However, it's important not too put too many fish in one tank. An overcrowded aquarium is likely to have a lot of problems, including:

  • Dangerously high ammonia and nitrate levels
  • Insufficient oxygen
  • Stunted fish growth
  • High risk of stress and disease
  • Fish behaving aggressively towards one another


Sick marine fish

Just like humans, fish sometimes get ill. There are all sorts of diseases that can affect the inhabitants of your marine aquarium, and some are more dangerous than others.

In today's blog post, we're going to look at some of the most common marine fish diseases and the tell-tale symptoms that give them away. When it comes to treating sick fish, different diseases require different approaches, but remember the old saying: an ounce of prevention is worth a pound of cure. Keeping your tank clean and ensuring that your filter remains in good working order will give your fish the best possible chance of staying healthy and disease-free.


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