Maintaining Your Aquarium

Diving in to the nitrogen cycle.

Is it just us, or do the words ‘Nitrogen Cycle’ sound like one first-class trip to the Bermuda Triangle? Either that, or you’re swimming for the hills. Unfortunately, not understanding the nitrogen cycle can send your fish to the little plastic castle in the sky, which happens to about 90 percent of new fish owners. But no sinking feelings needed, pet-lovers, because the nitrogen cycle actually isn’t too tough to get your head around. In a clam shell: Fish produce waste, and your aquarium’s ecosystem develops over time, to cope with it. And throughout this, you’ll simply need to maintain the water quality of the aquarium.

Best of all, there’s a whole school of things you can do to protect your finny friends, and control the nitrogen cycle.

How the cycle works, fishies.

Haste makes waste, and so do fish. In fact, they’re reely good at it. And that’s great, because this is the first step to making the nitrogen cycle work.

So, how do your fish create all this wonderful waste?

  • Fish excrete toxic ammonia as part of respiration.
  • Decaying fish waste creates ammonia.
  • Uneaten food also produces ammonia.

Here’s what happens next: Special kinds of bacteria go to work on the ammonia, and turn it into nitrites (just as harmful, fishies). These are then converted into nitrates (slightly less harmful). Meanwhile, the bacteria needed for this process builds slowly on the surface of your filters and gravel. This can take four to eight weeks, starting from the day that you first add fish to your aquarium.

Keeping the cycle floating along.

Go slowly.
First, add a few hardy fish, or ones that can put up with changing water conditions. In our petspert opinion, no catfish; nothing less than 2 cm; and nothing overly expensive. Start with fewer fish than your aquarium can hold, then add any additional divers over a period of weeks. This will allow the ecosystem in your aquarium to readjust (re-cycle), in-between your new arrivals. Finally, take each step slowly, so the bacteria has enough time to multiply and break down the increasing amount of waste from your scaly sidekicks.

Make partial water changes.
It’s best to change 15–20 percent of your tank’s water, every two to four weeks. Each time you remove some of the water, the level of nitrates will go down.

Adding new fish into the loop.

How many aquarium fish to start with.
If you have a small tank, you should start with only one fish. But if we’re talking 50–70 litres, you can throw in at least three or four fish. It may not sound like much – heck, you might not even see the fish in the larger tank. But this is the safest way to get your aquarium going, and lessen your chances of fish going down the drain – along with your money.

When to add new pet fish.
Now, we’re not going to tread lightly, here: New fish might actually find your tank’s bacteria levels deadly – like fish out of water – unlike the original Orandas, now accustomed to the gradual changes in bacteria. So, a basic rule of fin – only add more little dippers if they look OK, and you’ve waited at least a week since the previous group. A couple of days could mean sushi. (Insert shell-shocked Afra Cichlid here.) By adding only a small number to your fish familia, the bacteria will readjust more easily. Even to Clown Barbs, if you can believe that.

Keeping the bacteria healthy. For reel.

Once the nitrogen cycle has completed the start-up phase, your aquarium will be able to detoxify the constant levels of ammonia and other chemicals – as long as you maintain the bacteria colony. Keeping the colony healthy (or increasing the amount of bacteria in the aquarium) can be done by the type of filtration equipment you choose. Swim on over to our filter section for the full can of worms.

Remember that with aquariums, fish live in their own waste. So, it becomes the responsibility of we pet-lovers to make sure our finny friends have healthy living conditions. By keeping up with water changes and cleaning every two to four weeks, you’ll actually have less work involved with your aquarium than you thought.

Example: A 50-litre aquarium only needs a 10-litre bucket (or 20 percent) of water changed every two weeks. This, and a quick wipe of the glass, is all you need to do on a regular basis. You’ll also want to check your filter media and rinse it in aquarium water, every second partial change. This will extend the life of the media, save you money, and keep your tank running swimmingly. Simply change the media as needed – and also depending on the dirt levels created by ol’ Crimson.

And for the love of fishies, never change all the water in the aquarium, at once. This can shell-shock your entire school, cause potential disease or a downward spiral straight down the toilet. Plus, your aquarium filter won’t work well, for a while. It’ll feel like starting all over again. Sink, sink, sink… But If you find your underwater world is quite dirty and more water needs to be changed, just do small water changes every third day, for a couple of weeks. This will allow time for the fish and bacteria to adjust, while reeling in the mess. And it shouldn’t affect too much of the aquarium’s water chemistry, in case you were feeling as worried as your Neon Tetra looks – at all times.

Congrats, pet-lovers. You’ve made through the entire nitrogen cycle, and are still splashing about. So, use what you’ve learned. You and your finny family will be a whole lot happier – and healthier.