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Currently I have 10 aquariums at home plus a handful of outdoor ponds.  I've also cleaned and maintained a lot of aquariums for clients.  When you're keeping up with a lot of tanks, you have to be efficient with your maintenance routine.  Below are three things I do when performing aquarium cleaning that every fishkeeper should pay attention to. I recommend doing each of these tasks on a monthly basis to keep your aquariums looking their best at all times. (Note: These tips assume you are already performing regular water changes: Read my post on why water changes are important)

Perform These 3 Tasks Monthly

Add these three tasks to your monthly aquarium cleaning routine to keep your aquarium pristine.  Its not necessary to do all of these aquarium cleaning tasks on the same day.  If you normally do two water changes per month, you can split these activities up and do a couple with each water change:

#1: Clean the Lid

Dirty Lid
This lid has algae growing on the underside

The lids of aquariums can collect some nasty stuff. I've seen a lot of filthy lids. Rotting piles of fish food, dust, and calcium buildup can collect on the top surface. Fish meal is the primary ingredient in most fish foods. Once wet, a few stray flakes can really stink up a room. Mold, algae, and bacteria can grow underneath the lid where its always wet. In addition to looking gross, this buildup can reduce the amount of light getting into your tank. The result can be your fish and/or plants not looking their best.

Magic Eraser
Magic Eraser

Personally I use a magic eraser to wipe down both sides of my lids every month. If possible I like to take the lid to a sink where I can rinse it off, but a clean wet rag or sponge will work too. If needed, white vinegar will remove a lot of hard water marks and other gunk. Just make sure you rinse any cleaning products off with fresh water before replacing the lid.

#2: Clean the Glass & Rim

This one probably seems obvious but you should clean the (exterior) glass of your aquarium once in a while. A few water marks on the front of an aquarium can make it look dirty, even if you hardly notice them. I apply windex or white vinegar to a rag or paper towel and wipe off the glass. You don't want those chemicals in your aquarium, so don't spray them directly onto the glass.

The rim on the top of your aquarium also needs to be cleaned regularly. This is where water spots will slowly form into big white or yellow sheets of flaky, crusty calcium buildup. I've seen some neglected tanks that had a thick layer of calcium that took a lot of work to remove. This is also another spot fish flakes like to get stuck and start rotting. All of that can be prevented if you wipe the trim clean with a wet rag on a regular basis. If you already have the lid off the tank to perform a water change (and clean the lid), that's a perfect time to go around the perimeter with a rag and remove any gunk.

#3: Clean the Filter

The exact maintenance you perform is going to depend on what filtration you are running. I've summarized below what should happen on a monthly basis with a few of the most popular types of filters.

Sponge Filters:

Sponge Filter

Just squeeze it out. Sponge filters should be squeezed out in a bucket of aquarium water. This is easy to do during a water change. The water should be brown after a few squeezes of the sponge. You can use this dirty water to feed houseplants or your garden. Fish waste is mostly nitrogen, which makes it an excellent fertilizer. You don't need to replace sponge filters unless they start falling apart.

Hang On Back Filters:

Check the flow on your HOB filter, if you have an intake sponge on it, squeeze it out. Clean the filter intake if there is any visible buildup. You don't necessarily have to clean or replace the media inside your HOB filter every month. The filter media should be cleaned or replaced when the flow is being reduced or the filter cartridge is visibly full of gunk. Sponges and ceramic media do not need to be thrown away, they can be rinsed off in aquarium water and re-used for several years. For tips on improving your hang on back filter: read my post on DIY aquarium filter hacks.

Dirty Media Basket

Dirty Media Basket

clean media basket

Clean Media Basket

(My favorite hang on back filter is the Aquaclear line. You can checkout my writeup on why these filters are so great here.)

Canister Filters:

Cleaning a canister filter is very similar to a hang on back, just a little more work. I work with a bucket next to me to load the media baskets into when I open up the canister. Replace disposable mechanical media like poly floss if needed, squeeze out sponges, and gently rinse ceramic media. Biological media baskets usually don't need to be cleaned every month. Consider alternating them so each basket gets cleaned once in a 2-3 month cycle. The frequency at which your biological media needs cleaned will depend on the tanks bioload. Some setups will be able to go 6 months without maintenance, and some will need to be cleaned every month. The goal when cleaning biological media is just to remove buildup, so that the surface of the media is exposed to the water flowing through it.

Keeping your lid, glass, and filter clean by adding them to your monthly aquarium cleaning routine will keep your aquarium looking its best at all times.

Seachem Purigen is a synthetic absorbent that captures organic waste in the water column. It can absorb and trap nitrogenous organic wastes that would otherwise release ammonia, nitrite, and nitrate. Tannins from driftwood and other natural decor in the aquarium are also captured. Eventually, Purigen will turn dark brown to black, as shown in the photos below. But you don't have to discard it and buy more at this point, because Purigen can be regenerated and reused!

Used Purigen Bags
Used Purigen Bags

The Purigen packet on the left in the above photo was used for just a few weeks in an aquarium with some large pieces of driftwood. The brown color is due to it absorbing tannins from the wood in the water. The packet on the right was used in a different aquarium for several months.

Recharging Seachem Purigen

Basic directions for re-charging Purigen are available on Seachem's website. A screenshot of their instructions is included below:

Seachem Purigen Regeneration Instructions
Seachem Purigen Regeneration Instructions

Bleaching Purigen

I recharged two 100 ml bags of purigen using a solution of 2 cups Clorox bleach and 2 cups water in a plastic container. The bleach burns off organic material that has been captured by the Purigen. You can see the brown and green coloration was completely removed from these two bags after 24 hours.

Bleached Purigen Bags
Bleached Purigen Bags

Dechlorinating Purigen

After soaking for 24 hours in the bleach solution, I mix a solution of 2 cups tap water and 1 TSP of Seachem Safe. Safe is the same thing as Prime, but it comes in a dry powder form and 250 grams treats up to 60,000 gallons. Compare that to a 500ml bottle of Prime, which treats only 5,000 gallons. Per Seachem's instructions, you can use any equivalent dechlorinator, just be sure to use a large enough dose to remove all chlorine.


This is the first time the packets shown have been regenerated. After multiple uses, Purigen will begin to show staining or discoloration. I don't recommend re-using it more than 3 or 4 times.

Buy Seachem Purigen on Amazon


Adult Yellow Tiger Endler Males
Adult Yellow Tiger Endler Males

I recently purchased a few pairs of adult yellow tiger Endler's livebearers. The photo above is a couple of the males in my planted 10 gallon display tank. The best thing about livebearers is how easy they are to breed once you have a pair of adults with good genetics. I set up a simple fry rearing tank, added a very pregnant female, and within 24 hours of moving her I had 15+ newborn Endler fry.

Female Endler After Giving Birth
Adult Female Endler

Tank Setup

Fry Tank Setup
Fry Tank Setup

This setup is optimal for rearing young fish, whether they are livebearers or egg-layers. It requires no substrate and no decorations. All you need is a heater, a filter, and some moss or other plants for the fry to hide in. I am using a 20 gallon "long" size tank, which is shorter vertically and longer horizontally than a typical 20 gallon "high". The light is a 30" Nicrew LED, although a light is not required for raising fry.

1 Day Old Endlers in Java Moss
1 Day Old Endlers in Java Moss

These baby Endlers will be fully grown and ready to breed in about 3 months.


Bacto-Surge Sponge Filter
Bacto-Surge Sponge Filter

I'm using a Bacto-Surge sponge filter in this fry tank. A sponge filter is by far the best type to use in a tank with very young fish. Hang-on-back and canister filters have intakes that will suck up and kill newborn fry. Although you can use intake sponges on these types of filters, its much simpler to use an air-driven sponge filter. A 5 watt air pump can drive multiple sponge filters, filtering more than one tank with less electricity than a single hang-on-back.

Bare Bottom

Although you could put gravel into a tank you are using to raise fry, it is much better to run a bare bottom tank. I painted the back and bottom of this tank using black acrylic paint. The bare bottom allows you to easily vacuum out uneaten food and waste to maintain high water quality for the young fish. Having no substrate also saves you about $20 in a 20 gallon tank like this one.


Plants, such as guppy grass or java moss, provide the fry (or eggs) with a place to hide from their parents, who will often eat their own young. Additionally, plants provide fry with a high surface area to graze on infusoria, which are minute aquatic creatures such as ciliateseuglenoidsprotozoa, and unicellular algae.

Java Moss
Java Moss

I pulled a large quantity of java moss out of another tank that I was rescaping specifically for this setup. You can see several 1 day old Endler fry hanging out beneath the moss in the photo below. If you don't have access to such a large quantity of java moss, guppy grass, also known as najas grass, is often available at local fish shops.

1 Day Old Endlers in Java Moss
1 Day Old Endlers in Java Moss

Feeding The Fry

I feed newly hatched brine shrimp to all of my young fish. Brine shrimp are cheap to produce and can be hatched from eggs in 36 hours. They are small enough for newborn Endlers and Guppies to eat, high in protein, and irresistible to most fish. Fry that are raised on live brine shrimp will quickly outgrow fish that are fed only crushed flakes or other prepared foods. The photo below shows a culture of brine shrimp ready to be harvested.

This post has more information on hatching brine shrimp.

Live Baby Brine Shrimp
Live Baby Brine Shrimp

Update: Endler Fry Tank 5 Months Later

After setting this tank up I added dwarf water lettuce which has spread to cover most of the surface. The java moss has more than tripled in size and now hosts a colony of blue dream shrimp in addition to multiple generations of Yellow Tiger Endlers.

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