How to Make Your Aquarium Water Crystal Clear (+Why It's Cloudy)

How to Make Your Aquarium Water Crystal Clear (+Why It's Cloudy)

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You’ve probably seen aquarists with crystal clear water, but all they say to do is have proper filtration or use carbon and clarifiers, which is true, albeit none of them tells you how to start and maintain a clear aquarium for the long haul.

Plus no one tells you there are several factors why your water does not look so great.

Maybe you’ve got tannins from driftwood that make aquariums look like tea, or you’ve got a bit of algae bloom that cause fish tanks to be murky and green.

Sometimes it might even be just particulates from substrates or leftover food floating around and causing your water to look discolored and filthy.

In this article I’ll give three quick solutions that might help with your not so clear aquarium water.

We’ll also look at various causes of cloudy fish tanks, some preventative measures and recommended solutions for each instance.

3 Solutions to Clear Aquarium Water Quickly

Please note if these remedies do not work, you will have to dig a little deeper into the cause of your water clarity problem and find the best solution for it, which we’ll still look at a while later.

Solution #1

It is super important that you boost filtration when you have unwanted debris in your aquarium, so add filter floss, which you can cut to size and fit into your filter, or use micron (filter) pad instead.

Micron rating in filter pads is descriptive of how small the pores are on the pad material, with the smaller the pores, the smaller the micron rating and the smaller the particulates the pad will pull out of the tank.

Compared to filter floss, pads are finer and trap smaller particles hence their other common name polishing pads. They remove fine particles giving the water a clear polished look, whereas filter floss traps larger particles.

This then means you may want to use floss before pad rest your pads block up easily. Most filters also have their proprietary pads, which are perfectly fine and work well.

Note that pads and floss don’t last long because they pull out a lot of junk in quick succession, so make sure you change them after a week or so and put in new ones.

Solution #2

Use some aquarium carbon into your tank.

What carbon does is pull out tannins from water if you have any, as well as other chemicals that might be causing coloration in your water.

The carbon will even pull out odors in case your aquarium water stinks for whichever reason.

You can get it in lose format, and either put it in a filter pack then drop it in the filter, or stick it in your aquarium if you don’t have enough room in the filter.

Even so, using the filter is best because that way you force your aquarium water through the carbon which then makes it more efficient.

If you don’t want to do it this way, you can also get a carbon-infused poly pad which has the carbon built right into it and is easy to cut and fit into any filter.

That said, it important to note that most filters also have their proprietary carbon pads, so you can go ahead and use that instead.

Solution #3

The final, and a quite important solution is to add a water clarifier in your tank. By itself, a clarifier can only do so much, but when used together with carbon, floss, and pad filters, the process can be very effective.

Aquarium water clarifiers act as a flocculent, which means they stick little particles that would normally pass through filter media and make them bigger to a size that can be easily trapped.

Combining the three solutions works extremely well especially if you have something like a dinner party coming up and want your aquarium looking perfect as quickly as possible.

The whole system (carbon, filter floss, micron pads, and clarifier) can have impressive effects within 24 to 48 hours.

Why is The Water in Your Fish Tank Cloudy

Since adding carbon, floss, pads, and clarifiers may not be a lasting solution, it’s imperative to establish what sort of cloudy water you are dealing with.A topic I’ve covered comprehensively in this article first.

For this reason, I’m going to start basic so forgive me if this information is too obvious for you; hopefully, someone with lesser experience will benefit.

Algae Bloom

An algae bloom is simply a rapid accumulation of algae in aquarium water. Algal bloom can affect both freshwater and marine tanks and in most cases consist of cyanobacteria, though a single or small number of phytoplankton species may also be involved.

Mostly, the presence of algae results in green discoloration of aquarium water, though the color may also be red or yellowish-brown depending on the species of algae you’re dealing with.

Excessive nutrients in the tank, particularly phosphorous, is the main cause of algal bloom in freshwater tanks. Carbon and nitrogen can also cause algae bloom albeit to a lesser extent.

These nutrients mostly result from the build-up of organic waste in the water column and substrate from leftover food, fish waste, and even plant debris in some instances.

Bacterial Bloom

Bacterial bloom is another common cause of cloudy water in fish tanks, only that this time the aquarium will only be cloudy but without the green tinge.

This bloom is quite common in new aquariums, hence is sometimes referred to as new tank syndrome by experienced hobbyists.

The clarity of the water is significantly reduced due to floating particles that are not singly visible to the naked eye, but when viewed collectively, combined with other floating detritus and dust, they form a cloudy or milky effect in the water column.

Bacterial bloom mostly occurs before a colony of beneficial bacteria establish during the cycling phase of a new aquarium. At this point, the microbiology balance has not established as the aquarium is still young, and the environment inside the tank has not gone through the whole nitrogen cycle.

During this phase, there might also be pronounced algal growth, but this is no reason to fret. Besides bacterial bloom typically goes away on its own once the parameters in the aquarium have stabilized.

Gravel Residue

If the water in your aquarium is cloudy immediately or within an hour or two of filling the tank, it is probably due to insufficiently washed gravel.

To remedy this, you should empty your tank and clean the gravel thoroughly under a tap. Don’t stop until the water is clear.

Fill the tank once you place back the gravel back in.

That said, while washing the gravel, make sure you leave a chunk unwashed to help useful bacteria to recolonize the tank and keep it safe for fish to live in.

Driftwood Tannins

Tannins are present in driftwood, and over time they will leach into the aquarium water, staining it yellowish-brown or what seasoned aquarium owners refer to as a weak tea color.

Tannins also lower the ph of your aquarium water and soften it. For some fish, particularly species native to the amazon river basin, this may be desirable and even recommended, but it is not desirable when keeping other species.

To remedy this, soak or boil your driftwood before placing it in the fish tank to remove excess tannins that’ll otherwise stain your water. Moreover, consider using driftwood types like sandblasted manzanita that don’t leach as much.

It imperative to note that most hardwoods used in aquariums such as African Mopani and Malaysian driftwood leach, while untreated softwood rot quickly and alter the water chemistry.

Dissolved Chemicals

A high content of dissolved chemicals is another reason the water in your tank might go white or gray. The most problematic chemical being silicates, phosphates, and heavy metals.

A good way to deal with chemicals is introducing a conditioner that will reduce the ph in the tanks, which will otherwise be too alkaline (high ph).

Also, consider using reverse osmosis (RO) water in your tank for a more effective solution.

How to Stop Cloudy Water in Fish Tanks

Now that we’ve looked at some of the most common causes of cloudy water in aquariums, how do you then stop it from forming in the first place?

Again, it will depend on the cause, but below are a few preventative measures that are particularly effective.

Do Nothing and Let Nature Take it’s Course

I know this sounds ridiculous at best, but this is the recommended approach for new tanks. However, if you’ve had your aquarium for a long minute, you definitely want to intervene with another approach.

In a new tank, we assume the kind of cloudy water situation you are dealing with is bacteria and algae bloom, which is part of the cycling process. Once the Nitrogen cycle comes full circle, the problem will most likely resolve itself.

Choosing to clean the tank and filter will only disrupt the few beneficial bacteria that have had a chance to establish.

You want these good guys around because they eventually out-compete the cloudy water bacteria for food, starve and break them down.

Add Live Plants

This remedy is especially true when dealing with algae bloom. Adding plants will help reduce the number of nutrients in the substrate and water column that aid algae to thrive.

Live plants consume ammonia and nitrates generated by fish waste and uneaten food, which mostly build up in newly setup tanks before nitrifying bacteria become established, or in aquariums with a not so effective filtration system.

Also, aquarium plants have good bacteria and other microbes on them, which help initiate a biological in the aquarium.

Clean Your Filter Regularly

A dirty filter will not clean your fish tank as it should hence leave a ton of waste that acts as a food source for algae.

Usually, if you are not overfeeding your fish, and you’ve not overstocked your tank, the filter cartridge on a power filter should last one month. However, when you see a noticeable decrease in water flow, you should probably change it sooner and clean the filter if possible.

Even so, cleaning a new filter or replacing the pad before 30 days of installation will potentially eliminate the good bacteria trying to form.

Don’t Overfeed, Don’t Overstock

Excess food in your aquarium water aids algae growth, plus food particles float around the tank making it filthy and cloudy.

On the other hand, an overstocked tank will have fish producing more waste than the filter and water changes can remove in good time. That means ammonia and any other elements either from fish waste or a hard water source will accumulate and feed algae, which then results in a cloudy aquarium.

Mostly, we recommend having a gallon of water for every inch of fish you have. Moreover, when keeping dirtier fish like oscars or goldfish, you may want to have more water space per inch of fish.

Eddie Waithaka

Resident Content Creator and Marketer at AquariaWise who talks about aquariums and fish and aquascapes a lot.

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