3 Ways To Completely Flush Your Fish Tank

Flushing a fish tank isn’t as bad as it sounds. In fact, it can be very beneficial for your fish and may be done when ammonia levels are very high, or even just when there isn’t an emergency just to get all the old water out and put in the new water. This doesn’t actually take out all the beneficial bacteria though (if your tank is cycled) as most of the beneficial bacteria is in the filter. Flushing can be a good tool in helping your fish, especially if they’re is suffering from ammonia poisoning.

What do you mean by “flushing a fish tank?”

Flushing a fish tank is basically taking out all the water in your fish tank, without taking out the fish. You could always scoop out the fish and completely take out all the water, but this isn’t really fun for the fish, and for you especially if you have multiple fish in your tank. Instead, you can perform multiple water changes, but there’s even more than just that when flushing an aquarium, and we’ll be going into that later in this article.

Why would I flush my tank?

One of the big reasons why is to take away ammonia as I stated earlier. You could also do this if your fish has a disease to see if that could help.

How can I?

If you believe your fish will benefit from a complete flush or you think it would be time for one, you can follow these steps.

Step 1. Do a 50% water change, however when you add water conditioner, use the same amount of conditioner that you should use for your ENTIRE tank when it is full (for an example, if you are flushing a 10 gallon, use the same amount of water conditioner to treat 10 gallons of water) and only add back in half of the conditioned water and wait 15-30 minutes and then add the remaining into the tank.

Step 2. After you did the 50% water change, do another 50% water change again, but don’t do it in two steps (do it how you would normally do a water change).

Step 3. You can now wait an hour and do 2 or 3 more 50% water changes.

Step 4. Test for ammonia, if over .0 ppm, do more 50% water changes as necessary.

WARNING!: PLEASE READ! If your tank is CYCLED, DO NOT TOUCH the FILTER MEDIA through this process! Not touching will help keep the good bacteria intact in the filter.

Unfortunately, the only problem with flushing an fish tank is that it takes time and takes a lot of water conditioner in total. But luckily if you don’t like how that method was, here are two other ways.

A second method

Here is another way to flush an aquarium.

Step 1. Do as you would with step 1 for the first method.

Step 2. Follow that with another 50 water change.

Step 3. Wait 30 minutes and perform another 75% water change, repeat with 50% water change to make sure the water is completely gone.

Step 4. Test the water for ammonia. If higher than .0 ppm, follow with another 25-50% water change, repeat as necessary.

So, there’s yet another way to flush a tank. Again, as long as the old water gets completely taken out of the tank and the fish are stress free as possible, that should be fine. If you don’t like that method either, here is one more.

WARNING!: PLEASE READ! If your tank is CYCLED, DO NOT TOUCH the FILTER MEDIA through this process! Not touching will help keep the good bacteria in the filter.

A third method

This is third and last method we will talk about in this article.

Step 1. Perform a 25% water change, use water conditioner for the entire volume of the tank. For example, if you have a 10 gallon aquarium, but only taking out 5 gallons, add 10 gallons worth of conditioner to the new water. Add 50% of the water and wait 15-30 minutes, and add the rest in.

Step 2. Follow the two water changes with another 50% water change. Wait 30 minutes and perform one last 50% water change.

Step 3. Test the water for ammonia, if over .0 ppm (parts per million), continue with another 50% water change, repeat as necessary.

WARNING!: PLEASE READ! If your tank is CYCLED, DO NOT TOUCH the FILTER MEDIA through this process! Not touching will help keep the good bacteria in the filter.

Flushing a tank is a great way to deal with ammonia, you could also flush your tank if your fish has a parasite such as ich. It will help to take out some of the ich parasites in the aquarium. Some fishkeepers do flushes as frequently as every month in order to keep the water clean and take out all the old water.