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Video:How to Change Water in Aquariums

with Dan Thornton

Water changes are necessary to maintain a healthy freshwater aquarium. Watch this how-to video from About.com to learn the correct way to change your water in your home aquarium.See Transcript

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Transcript:How to Change Water in Aquariums

Hi, I am Dan Thornton, owner of Reef Encounters in Erie, Colorado and I am here today for About.com to talk about how to change water in aquariums.

Water Change Frequency in Aquariums

 To determine how often to change water and how much water you need to change, you should be using your nitrate tests. If you are testing for nitrates every week, which I would recommend you do, and you keep a log of those, you should be able to keep track of when they are increasing. If they are increasing, then you are going to need to change more water, or change water more frequently. The nitrates themselves may not be causing much harm to your fish, but they are a good indication that there are things building up in the tank that you are not testing for, and by doing water changes, you are diluting those things too.

Before you start changing water in your aquarium, you want to unplug things. Generally, about thirty percent of the tank once a month is enough water. If you have a normal amount of fish in there and you are feeding them correctly.

Cleaning the Aquarium

I like to do my water changes at the same time that I clean the algae. What I will do is take enough water out so that I can clean the tank without splashing water over the sides, and then do all of my cleaning, and then take the rest of the water out. So maybe take 10 percent first, get in there and clean all the algae, clean your filters, and then do the other twenty percent. And sometimes you can save some of the water in a bucket for filters that need to be cleaned outside of the aquarium.

Know the Water Chemistry

If you want to take sponges out you can put it in the bucket and squeeze them. That way you are using the aquarium water to clean the filter, and you don't have to worry about killing the bacteria that are on the filters.  If you just use tap water, then the chlorine or chloramine in the tap water will probably kill the bacteria on your filters.

When taking water out, it's a good idea to vacuum the gravel, just use a regular gravel vacuum, just kind of twist it into the gravel, and you leave it there until the water running through it is clear, and then you move it to the next spot. You can do this with buckets, or you can hook a hose up to a water source. Either way, it is pretty much the same thing, you are just adding fresh water back into the aquarium. If you are using a hose, it is best to let the water pour in on top of the water, that allows some of the gases that are in the tap water to come out.

You need to know when you are adding water, whether or not you have chlorine, or chloramine. If it is chlorine, than use something to neutralize the chlorine. Chloramine is a combination of chlorine and ammonia, and it is actually much more dangerous than chlorine.

Thanks so much for watching. For more information on fish, please visit us at About.com.

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