Aquarium Cycling- Freshwater

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Lots of people want to have their first aquarium, most people don’t understand how to cycle their aquarium correctly. Cycling an aquarium is something that some fish stores fail to inform new customers about. I say this because I was one of these people, when I started. Got it stuck in my head that I wanted an aquarium and ran down to the pet store. Purchased my first 20-gallon tank kit that came with tank, filter, light and substrate. Took it home set it all up and added the water, it looked amazing! Next day I head back to the same pet store and purchase some fish, just the ones I liked- two days later they are all dead.

If you are looking to get a new tank keep reading and learn from my mistakes, also do more research other than this.  Each fish has specific water parameters that need to be met to provide them a happy life!

Little did I know, that the reason my fish kept dying was because my tank had not been cycled. The fish I purchased were going from quality cycled water to chlorinated water and water that was still fluctuating so much the fish could not survive in it.

A fresh water test kit, either one that’s just strips or a master test kit that is more involved will be needed. In order to determine ammonia, nitrate, and nitrite levels in your water to determine if it has cycled properly. I suggest the master test kit, although more expensive it is more accurate.


Cycling with Fish

Aquarium FIsh
Zebra Angelfish

There is two ways to cycle your aquarium, with fish or fish less. There are some hazards with the fish option. You run the risk of exposing your fish to ammonia and nitrites that are harmful, if done correct it is the faster option. I like the general rule of 30 day and then checking my water parameters for that last check.  Checking water parameter should be happening at least every week to determine where you are in the process.

Cycling your aquarium with fish works how it sounds, you add fish to a de-chlorinated tank and allow their waste to create the ammonia and nitrite needed for the beneficial bacteria to grow. With my example above I should have added 2-4 fish for my 20-gallon tank.

Feed your fish very little at first, so you don’t create a rapid rise in in ammonia. The fish will create waste on their own you don’t want to be adding more with uneaten food.

Next, is ensuring you are doing proper water changes every 2-3 days. Doing 20-25% water changes in this time frame will help reduce the stress on the fish from the ever-growing ammonia in the tank.  I suggest doing 20-25% water change on cycled tanks anyways to provide the best conditions for your fish at all times, if you have fish fry it will assist with their growth as well.

To monitor your ammonia, nitrate and nitrite levels you will need to purchase a test kit. These can be bought at most pet stores and are fairly easy to use. Most come with instructions on how to use them; they can be expensive, but well worth the investment.

Ammonia is first created by fish or food waste, then nitrite is created when beneficial bacteria break down the ammonia. Nitrate is the final step in the cycle and should be below 40 ppm.

You can begin adding more fish to your tank when ammonia and nitrite are at 0 ppm and nitrate is below 40 ppm. A word of caution here do not add to many fish at one time, slowly introduce them. If to many fish are added too quickly you can still get an ammonia spike.

Cycling without Fish

Fishless Cycling

Fishless aquarium cycling just add a few flakes of food into the tank every 10-12 hours. Once the flakes begin to decay it will create the ammonia for the process to begin. Every few days check the ammonia levels. Once you get an ammonia reading of around 3 ppm, continue this for a few weeks and check your nitrite level.

This can also be done by using an ammonium chloride solution, when added will act like decaying food to start your cycle.

Ammonium Chloride Solution for Fishless Cycling
Ammonium Chloride Solution (affiliate Link)

When you first detect nitrites, you know the cycle has begun, continue adding flakes to the tank. After a week you should start to see your nitrite levels begin to drop, now is the time to start testing your nitrate levels.

Once your ammonia and nitrite levels reach zero and the nitrate levels are 40 ppm or lower the cycle is complete. As with above, slowly add fish to your tank if you add too many to fast the ammonia will spike and create an unhealthy environment for your fish.

You do not want to stop testing your water parameters when cycling your aquarium is complete, this is a constant process that needs to be completed to ensure your fish are living in the healthiest environment possible.  The less stress on the fish in your aquarium the better. 

Keep It Fresh!

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