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How To Clean A Fish Tank – Complete Guide

If you want your fish to remain healthy, you must keep your fish tank spic and span. Listen to any advice about raising fish, whether it’s from your local aquarium store or from a website like hours, and time after time, you’ll hear how important it is to maintain a clean aquarium.

Why? Poor water quality can be detrimental to the health of a fish, even leading to a number of diseases and fatal conditions. When the nitrate and nitrite levels in your tank rise (which happens naturally as fish produce waste and increase the bioload in your tank), your fish can become sick over time.

Cleaning your tank and conducting regular water changes is the best, easiest, and most cost-effective way to keep your fish healthy. Why treat with expensive, side effect-inducing chemicals when you can prevent an outbreak of disease altogether – just by cleaning your tank?

Unfortunately, many people assume that removing all of the water in their fish tank and starting with entirely new, fresh water will be the best way to clean their fish tanks. Unfortunately, this is simply not the case. Engaging in regular routine maintenance and conducting partial water changes is the best way to improve the health of your fish tank.

Why? Removing all of the water from your fish tank kills all of the good, beneficial bacteria that has accumulated in your tank. Remember, the larger and more occupied your tank is by these good bacteria, the easier it is to keep your tank fresh and healthy.

Here are some tips for cleaning your fish tank, along with the best advice for getting started.

How To Clean A Fish Tank

The Importance Of A Clean Fish Tank

We outlined the importance of a clean tank in the introduction to this article, but the benefits of a clean tank cannot be overstated. For starters, a clean tank will help you meet three specific goals when you are raising fish.

To begin with, cleaning your tank will regulate the nitrogen cycle. Why is this important? The nitrogen cycle is how ammonia is switched to bacteria, then to nitrite, and then to nitrate. Ammonia and nitrite are extremely toxic to fish, and you need some bacteria in your tank to convert these harmful compounds to nitrates, which are much less harmful and can be easily removed by water changes.

Whenever you introduce fish to a tank, you must first make sure it has been appropriately cycled. You can accomplish this in myriad ways, but one of the easiest and most effective is to add artificial ammonia to increase the numbers of beneficial bacteria in your tank.

Second, a clean tank will remove any dissolved organic compounds. This sounds complicated and scientific, but it’s actually quite straightforward. Organic compounds are those that are comprised of hydrogen and carbon. These might include things like fatty acids, amino acids, and even vitamins. Organic matter can either be dissolved organic matter or particulate organic matter.

Organic matter is essentially waste. You will have organic matter in any tank where fish are regularly fed – so any aquarium tank. Organic and food waste are broken down just as ammonia is in your fish tank – by these beneficial bacteria.

Remember that plants can help absorb some of the load from organic matter, too. Developing a heavily planted tank and conducting regular water changes can reduce the build up of organic compounds in your tank.

Finally, a good, thorough tank cleaning will help replenish lost minerals in the tank. It can also balance out tanks that have too many minerals. Too many or too few minerals can cause something called osmotic stress in fish, which can ultimately cause permanent shock and then death.

When you add water to your tank, it is not uncommon to add reserve osmosis-filtered water. This removes the impurities of tap water, which is a good thing for tanks, but it also gets rid of the minerals that your fish rely on for good health. When you clean your tank, you can add all of these essential minerals back into your tank without compromising the health of the rest of your tank.

Here’s How To Keep Your Aquarium Clean At All Times

Want to know how to keep your fish tank clean – and to avoid falling behind on your chores? It’s easy to stay on top of your aquarium-cleaning chores by implementing a few simple daily and weekly tasks. By breaking your chores down into chunks, it will be much easier for you to stay on top of your duties.

For daily tasks, you only need to commit to a few minutes every day – and who doesn’t have time for that? Start by implementing a regular feeding schedule. Feed twice a day, and remove uneaten food after about five minutes. This will reduce the likelihood of uneaten food breaking down and negatively impacting your water quality. Watch your fish carefully and only feed them as much as they can eat in one feeding. Overfeeding can cause a number of other health problems, too, so you aren’t doing your fish any favors by giving them extra food.

You should also inspect your fish on a regular basis. Do they seem healthy? Are they eating enough? Are they swimming or otherwise behaving okay? Do they show any outward signs of illness or injury?

Finally, monitor the water temperature and depth of the water on a daily basis. You can also measure the pH and hardness of the water daily, but this will likely be more time consuming to do. Water temperature is the most important parameter to keep an eye on, and you can easily fix it if it is not within a desired range.

On a weekly level, you will need to check your pH, salinity (if applicable), and nitrate, nitrite, and ammonia levels. Again, while these can be done more frequently, you should at minimum do it once a week. You can have your water tested at the local aquarium store, or you can just buy a home test kit. These are easy to use and basically consist of color-coded strips of paper to help you evaluate the specific levels in your tank.

Once a week, you should also do a once-over of all of your equipment. How does your filter seem to be functioning? What about the lights? Make sure everything is working the way it should, and fix or replace any faulty or malfunctioning equipment.

When Do I Need To Clean My Tank?

Unfortunately, there is not one hard and fast answer to this question. How often you should clean your tank depends largely on the size of your tank, as well as the quantity of fish you have live-in in it.

Generally speaking, however, you should try to conduct a partial water change at about 10 to 20 percent every two or three weeks. If you have a saltwater tank, the recommendation is a bit different – you should change ten percent of the water every week for the first year that you have the aquarium. After the first year, you can adopt a freshwater tank cleaning regimen.

Remember that the more fish you have, the larger the bioload on your tank will be, and therefore you will need to clean your tank more often. Smaller tanks also become dirtier more quickly than large tanks, so it’s important that you monitor your tank to understand how often it needs to be cleaned.

Again, your tank cleaning requirements and specific needs will vary widely. Researching the fish and other species that you have living in your tank will help you get a better handle on the parameters they require.

In general, you should remember that freshwater fish require temperatures between 72 and 84 degrees Fahrenheit, with pH values of 6.5 to 7.5. Alkalinity should hold steady between 4-8 KH, with hardness between 4-12 GH. You should have zero ammonia or nitrites in your tank, and nitrates should remain at fewer than 50 ppm.

For saltwater, temperature should hover between 72 and 82 degrees Fahrenheit. pH should be between 8.0 and 8.5, while alkalinity should be between 6 and 12 dKH. Specific gravity should be around 1.020-1.025, while there should be no ammonia or nitrite levels detectable. Nitrate should be less than between .25 and 30 ppm. You will also need to keep an eye on the calcium, magnesium, iodine, phosphate, and strontium levels in your saltwater tank.

All of these numbers fluctuate and can vary depending on certain circumstances. For example, if you have a brackish or pond environment in your freshwater tank, you may find that your water temperatures can be a bit higher or  lower, as can your alkalinity measures. In saltwater tank, the differences between reef and coral reef aquariums are also pronounced. Therefore, it’s important that you conduct thorough, detailed research for your specific tank environment before getting started.

Preparing Your Tank For Cleaning

When you’re ready to clean your tank, you should first gather the appropriate supplies. Many of these can be improvised or DIY-ed using items at home, but usually, it’s better to purchase the required equipment so that you don’t have to worry about contaminating your freshly cleaned tank with outside bacteria, viruses, and parasites.

Here is what you will need to clean your tank:

  • A used cloth or rag (clean)
  • A large bucket (this should be dedicated solely to cleaning your tank)
  • An algae pad or scraper, like a magnetic cleaner
  • A vacuum designed to siphon gravel
  • Prepared water (the exact quantity will vary depending on your tank size)
  • A water test kit
  • A new filter media (optional)
  • Heater (saltwater only)
  • Powerhead (saltwater only)
  • Salinity probe (saltwater only)
Remember that most aquariums will be too heavy to move when they are filled with water. Trying to move your aquarium when it’s full is ill-advised, as it could cause stress and damage to your fish inside the tank. Instead, the siphon will allow you to remove water from the tank. The bucket, in turn, will allow you to replace the lost water from inside the tank.

Before getting started, make sure you remove any large decorations, ornaments, or artificial plants. You should unplug any electrical equipment in your tank, such as your filter, heater, and pumps.

If you have sensitive fish, you can remove them to a separate tank while you are cleaning, but in general, you should not disturb your fish during the cleaning process. You should remove artificial plants, as we mentioned, but live plants should not be moved as it can disrupt their roots and cause them to die.

When you clean, try to do so slowly, avoiding stirring up any debris or accumulated particles at the bottom of the tank. The substrate should stay where it is unless it, too, appears to be in need of a deep, thorough cleaning.

How To Clean Your Tank

When you clean your tank, you will need to remember that about ten to twenty percent of the water will need to be swapped every two to three weeks. Start by removing the water for the water change and cleaning the gravel. You can do this by using a siphon gravel vacuum, ideally one with a powerful hose. This will allow you to clean the gravel and to remove the water.

If you accidentally suck up small amounts of gravel, don’t panic – this is actually a good thing, as it will clean off the gravel. The waste will pass through the tube into the bucket, and they ravel will then fall back in its original place – but it will now be nice and clean.

Whatever you do, just make sure the gravel doesn’t fall all the way into the tube. You can use a finger to block the end of the tube. This will slow down the siphoning and make it less likely that the gravel will be fully sucked inside.

Some more expensive siphons have advanced features, such as regulators to adjust the flow of the water. There are some that have extended hoses so that you don’t need a bucket and can instead siphon your water directly into the sink. These aren’t necessary, but can make your job a little easier.

Removing Algae

After you’ve cleaned the water in the tank, you can progress to removing the algae. The amount of algae that you have in your tank will likely vary depending on factors like lighting and whether you have any algae-eating species in your tank.

However, the easiest way to remove algae is to use a magnetic cleaner. This will have two magnets and a soft felt cover. All you need to do is place a magnet on the inside of the aquarium, and let the other attach to the outside of the aquarium. Using the outer magnet, you can drag the interior magnet around the glass of the aquarium, allowing you to clean the tank without getting your hands wet. These devices are also nice because they don’t scratch the glass.

Decorations and artificial plants can be cleaned of algae, too. Simply place them in the bucket of water and use a clean brush to remove any algae. Don’t use any detergents or soap, as this can harm your fish no matter how well you think you rinsed them before putting them back.

Cleaning And Replacing The Filter

After You have removed the excess water and algae from your tank, you can then progress to cleaning and adjusting your filter. Sometimes, you will need to change the medium in your water filter too.

Most people use sponge filters, which can be cleaned by removing them and rinsing them in the bucket of water. You should avoid rinsing your sponge filter with tap water, as this can strip the beneficial bacteria form the surface of the filter. Remember, your fish need these beneficial bacteria in order to survive.

There are other kinds of filters, like ceramic rings or filter fibers, that can be cleaned, too. These should be closed in the same way you would clean a sponge filter, but remember to replace them as quickly as possible to avoid killing any good bacteria.

Filters that have ammonia absorbers, carbon, or ion-exchange resins will need to be replaced every few weeks. You won’t need to clean these, but instead put new ones in. any other filter components, like tubing, should also be cleaned on a weekly basis.

Replenishing The Water In Your Tank

Once the tank is nice and clean, you can move on to topping the tank back up with water. How much water and what kind will depend on the type of tank you have (saltwater versus freshwater) as well as how much water you removed and the overall size of your tank.

For a freshwater tank, you should leave tap water out for 24 hours. This will allow any chlorine or other chemical in your water to evaporate. You should use a water conditioner to remove any heavy metals, which can toxic to fish. Preparing your water a day in advance will also give it time to reach room temperature so that it won’t be too warm or too cold for your fish when you introduce it to the tank.

If you have a saltwater tank, you will have to do a bit more work to get your tank ready. For starters, you will need to be vigilant about temperature, pH, and salinity.

If you maintain a reef aquarium, you will need reverse osmosis or deionized water. This can be purchased at most fish stores, but there are also systems that produce this kind of water that you can purchase, too.

Only use tap water if you have an excellent local supply, and make sure you have tap water tested for total dissolved solids – the reading should be less than 10. Never use tap water in an aquarium that contains species other than fish.

As with freshwater tanks, you will need to remove chlorine from the water. Then, you should add a salt mix. Make sure you choose a reliable kind – table salt, obviously, just won’t do! Follow the instruction son the package to make sure you are mixing in these salts at an appropriate ratio.

Many salt mixes must be added to moving warm water. You can do this with the heater and powerhead you already have. As with a freshwater aquarium, try to have the water prepared a day in advance. When you add the water, make sure the temperature and salinity are as close to the previous conditions as possible to avoid any sudden shock to your fish.

For both a freshwater and saltwater aquarium, you should examine the water parameters a couple of hours after changing. Make sure the water is not cloudy, and that your fish are adjusting to the new water well.

Other Fish Tank Cleaning Tips

When you are done changing the water and cleaning the interior of your fish tank, remember that a clean fish tank isn’t excluded to just the inside of the tank! You should also clean the outside of your fish tank. This will help it look more attractive and will also allow more light to penetrate through the glass, so that your plants and fish will develop in a healthier manner.

You can do this by wiping down the tank with a cloth and a glass cleaner. You should not use any old glass cleaner but instead use one that is recommended for use on aquariums.

If you have a used tank, you should do some extra work to clean it before you introduce any fish. Use vinegar and salt or baking soda to remove hard water stains or lingering orders. Rinse the tank thoroughly before you add water, as you don’t want any of these items to upset your fish.

Before you introduce fish, you should add water and let it set for several days. This will help you determine whether the tank has any cracks or leaks. If you find leaks, don’t panic -you can easily fix these using aquarium sealant.

If you have eggs that were laid in your tank, be careful while cleaning. Avoid cleaning the gravel, where the eggs are most likely to be, until the eggs have hatched and you can see the fry. Because eggs tend to hatch quickly, this shouldn’t pose a major disruption to your cleaning schedule.

A Clean Tank Matters

Cleaning your fish tank should not be a stressful experience, but it should be on your weekly list of chores and to-dos. This important task will help keep your fish happy and healthy, and will also improve the appearance of the aquarium in your home.

So what are you waiting for? Grab your equipment, and get to scrubbing!

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