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.

If you're having odour issues and you're not how to fix it then don't worry we're here to help! In this article we'll talk you through some of the things that are likely to cause bad smells from your tank, as well as ways in which to prevent them from occurring in the future.


Why your fish tank smells

If your fish tank is maintained and managed in the correct way then it should never emit foul smells that can be identified from across the room, or other parts of your home. If you can then it's likely that your tank contains some sort of bio-waste that has not been removed.

Here are the main sources in which bio-waste occurs:

  • Too much food - Overfeeding your tank's inhabitants may seem harmless, but it will very likely be the cause of bad smells. All of the food that is left uneaten by your fish falls to the bottom of the tank. From here, it promotes an overgrowth of bacteria which release waste gasses leading to the bad smell. Additionally, your fish and corals will eat more and thus produce more waste, which in turn can cause odour issues.
  • Overstocked fish tank - No harm can come from filling up your tank with a lot of livestock, can it? Wrong! If too many fish are living in your tank, this means that a lot of waste is going to occur. When this happens, the helpful bacteria that work to keep your tank clean, as well as your tank's filters are unable to cope with the demand. This leaves a lot of fish waste sitting in your tank and ultimately leads to the bad smell you're smelling.
  • Dead inhabitants - Probably the most common cause of a really smelly fish tank is dead inhabitants, either fish, corals or critters. If you have appropriate clean up crew (shrimps, crabs, snails) then this should not cause a problem, but it can if you do not. When something dies in your tank it leeches proteins and oils, which will begin to come off and float to the surface. Once there, these gasses begin to evaporate out of your tank and into your home, causing a bad odour.


How to stop fish tanks from smelling

Once you have located and removed the source of the bad smell coming from your fish tank, there are a few simple things that you can do to ensure your tank's smell remains as pleasant as possible. These include:

  • Weekly water changes
  • Weekly cleaning of the filters and skimmer cup
  • Regular cleaning of the sump areas, to clean out excess build-up of waste
  • Feed your fish the correct amount, avoiding overfeeding
  • Occasionally use activated carbon media in your tank's filters

By following the guidance above, you will be making great strides to keep bad smells coming from your fish tank. If, however, you think that you need extra protection against bad smells with new equipment such as filters, you can browse our wide range of marine equipment below.

Shop Marine Equipment >

If you'd like to speak to a member of the Rock N Critters teams about the bad smell that is coming from your fish tank, be sure get in touch with us today. You can even pop down to our one-of-a-kind showroom if you'd prefer to chat to us in person - we'd love to help!

Photo from Flickr

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