Water Changes Necessary

Aquarium Water Changes Necessary? – Yes, Here’s why

Are aquarium water changes necessary? Absolutely! If you’re still unsure about how important water changes are I’m going to assume you’re pretty new to the hobby, and if so, you’ve come to the right place.

Water changes are the number 1 most important part of maintaining your aquarium. I’m sure you’ve already read a bunch of articles and seen a ton of videos on HOW to do water changes. There’s so many of those on YouTube, yes I’ve got one too, you can watch it right HERE.

But this article will help you understand what makes aquarium water changes necessary.


Aquarium Maintenance

So water changes, love’m or hate’m, are part of the hobby. Its part of the required maintenance. Luckily the majority of long term fish keepers eventually enjoy doing them.

Its part of the satisfaction knowing you’re taking care of your fish, you’re keeping their home clean. You’re keeping your guys happy and healthy! But why do these water changes need to be done in the first place?

Well your fish are living in a box of water. In that box is where they eat and create waste, or my favorite word, poop! That poop stays in their box of water with them and we as fish keepers have to remove it.

Now I know what you’re thinking, isn’t that what our filters are for?…well, yes and no.



Our filters do a few things. They mechanically filter your water which removes the physical waste, you know the actual pieces of poop. Along with other waste like uneaten food and particles floating around in your water. This is also the part of your filtration that gets you crystal clear looking water. 

But before your filters remove the physical waste from your aquarium the damage has already been done. That physical waste in the water and in your filter breaks down into ammonia which is a deadly toxin for your fish.

Ammonia is the number 1 killer of fish especially in a new tank. Its called New Tank Syndrome. And the only way to remove ammonia is by way of the beneficial bacteria growing in your tank.

The beneficial bacteria will convert Ammonia into another toxic byproduct called Nitrite, and then convert it again to a far less toxic byproduct called Nitrate. Without this beneficial bacteria in your system the ammonia stays in your water, with or with out a filter.

Our filters help to grow beneficial bacteria by way of the bio-media we put in them. This bio-media is where most, not all, but most of your beneficial bacteria will live on and grow on.

But this bacteria takes time to grow, which is why you’re not supposed to add fish immediately into a new tank. You’re supposed to wait for the nitrogen cycle to complete first. If you’d like more information on the Nitrogen Cycle – Here’s a great video!


Nitrates Make Aquarium Water Changes Necessary

So hopefully I haven’t lost you and you remember I said the last thing your bacteria converts ammonia into is called Nitrate. Nitrate is the final conversion in the cycle. Nitrates stay in your tank and can only be removed by you, via a water change.

If you keep fish like African Cichlids, they will produce a lot of waste which will convert to high nitrates quickly. In this scenario you would want to do bigger and more frequent water changes.

African Cichlid
OB Red Fin Borley – African Cichlid


Your filters will not remove nitrates. Adding another filter wont do it. Adding more bio-media wont do it. The only way to remove these nitrates successfully is by removing old water and replacing it with new water.

The only other thing that can HELP with Nitrates is live plants. Yes, live plants do reduce nitrates and can reduce how often you need to do water changes, but they wont eliminate nitrates. Live plants still wont substitute for a good o’ll fashion water change.


Dangers of High Nitrates

Even though Nitrates are far less toxic than ammonia or nitrite, its still toxic. And as your fish continue to eat and continue to poop, the ammonia increases, your bacteria converts it all, and that makes your nitrates increase as well. As your nitrates increase past 40PPM it begins to become harmful for your fish. It can stunt their growth, it can stop them from mating, it can cause stress which can easily lead to disease.

Which is why its important to test your water periodically until you get a feel of when your nitrates start to reach about 40 PPM give or take a few. Every tank is different, it all depends on your bio-load.

How many fish you have, how often you feed, how much you feed, how good your last water change was….all of that factors into how fast your nitrates reach about 40 PPM, which is a good indicator that it’s water change time. I say about 40PPM because some fish are hardier than others and can handle a bit more Nitrates while others can’t.


New Water Benefits

Along with removing nitrates, new water adds trace elements and minerals back into your tank that have been used up in your old water. As these trace elements get depleted by your fish it can drop your PH levels messing with the chemistry in your tank. It can also effect your beneficial bacteria’s growth and health.

By adding new water you are essentially replacing the elements and minerals that keep your fish happy and healthy! Now that you know WHY you should be water changing check out the video below on how to water change and clean your tank properly.

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