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One of the crucial parts of successfully keeping seahorses is finding a proper filtration system powerful enough to counteract their messy tendencies.
Seahorses are unlike other fish, these saltwater creatures expel a lot of waste and this can become problematic really fast if the right measures aren’t put in place.
The best filtration system for a saltwater species-specific tank is a sump system that combines mechanical, biological, and chemical filtration to produce a well-established filtration mechanism.
- Mechanical Filtration – The use of a powerful protein skimmer and socks/floss, or sponges.
- Biological Filtration – Cured live rock, substrate, or porous media.
- Chemical Filtration – Activated carbon or GFO ( Granular Ferric Oxide )
- Clean-up crew – An all-rounded compatible crew to help in the maintenance.
There are a variety of filtration systems that you can use for your tank, but the ones listed above are the most effectively used systems that aquarists and hobbyists have gotten the most success from.
When keeping seahorses it’s important to make use of all sorts of filtration systems to form a powerful system strong enough to combat their messy eating habits and waste expulsion tendencies.
Why Are Sump Filtrations The Best For Seahorse Tanks?
A sump is an additional smaller tank or vessel, normally positioned beneath the tank in a cabinet or behind the tank.
The sump can be a simple vessel outside the tank or it can be a purpose-built secondary tank that carries out different functions.
This vessel has many benefits for a saltwater tank and is probably the best filtration method that one can choose.
Especially for a seahorse tank where you will need a lot of additional equipment and systems, a sump is the best. Benefits include:
- A sump will give your system additional water volume diluting waste for more stable water parameters.
- Gives access to increased filtration since you will have more space for the installation of equipment and filter media.
- Gives a cleaner aesthetic since all the filtration systems used are hidden.
- It allows for a quieter operation if set properly.
- Sumps make it easy for regular maintenance and inspection to occur. This is important since maintenance in a seahorse tank is very consistent.
- Gives you the ability to use an in-sump skimmer which is more effective in removing waste.
- You have the option to add a refugium which helps greatly in harvesting good bacteria.
A sump is honestly the best way that you can effectively maintain a seahorse tank without having to deal with the challenges that come with maintenance.
In fact, all big tanks have a sump and it’s no secret why! you can get away with smaller tanks where you can use other filtration systems to get the work done.
But with seahorses where the minimum tank size should be around 30 gallons, having a sump just makes things easier to handle their bio-load.
If however, you looking for another option that will work beside a sump then an external canister option will work as well.
External canisters are much more accessible, inexpensive and they work by pulling in water via an internal pump, which then forces water through the various filter media found inside the canister and then back up to the tank
These external canisters come with a built-in system of different types of filtration necessary.
These canisters can be customized to suitable individual tank needs and will be a good alternative to the sump option.
Canisters do work just as well and will do a good job ensuring clean water, but because seahorses give off a heavy bio-load you will need to add additional filtration mechanisms to assist.
Ultimately sumps are superior although it takes more work and time to install it will be the best suited for the needs of a seahorse tank.
Saltwater aquariums require good water flow as well as low nutrient levels, and for that reason, sumps are generally regarded as superior in this case.
The Best Mechanical Filtration For Seahorses.
Mechanical filtration refers to water passing through a filter media trapping particles, debris, and uneaten food before it has broken down.
This is the most basic yet effective filter type that is used to get rid of unwanted solids floating around in the water.
Mechanical filtration is required as the first filtration type since they catch undissolved waste before it can break down.
Once waste is broken down harmful substances such as ammonia and nitrite are released. These substances are toxic to marine life and death is inevitable.
This is why mechanical filtration is so important as it acts like the first line of defense when combating detritus waste.
Types of Mechanical Filtration.
There are many types of mechanical filtration one can use, these include.
- Filter cartridges
- Filter floss
- Filter pads
- Filter socks
- Filter foam
- Fleece rolls
The most commonly used media are filter socks and fleece rolls. These work very well but they must be maintained regularly.
If not cleaned out, the waste collected in these filters can break down releasing harmful substances like ammonia and nitrite which are deadly.
Proper and regular maintenance is key when using these types of filter media.
Protein Skimmers.
A protein skimmer is another form of mechanical filtration that is a necessity when keeping seahorses. Even though it’s not a need, it would be foolish not to get one.
Basically, a protein skimmer or foam fractionator is a device used to remove organic compounds such as food and waste particles from water.
It works by whisking tank water and air together into a foam. That frothy mix of air and water filters the tank water and permanently removes broken-down food, waste, suspended particulates, and undesirable color pigments.
This removes the majority of the waste while working together with other systems to form a reliant network of filtration.
When choosing a good skimmer there are two types to choose from, regardless of which you choose from.
- Internal Sump Protein Skimmer – These skimmers are designed to be installed inside the sump powered by a single pump.
- External Protein Skimmers – These are water-tight skimmers that utilize a single pump and can only be mounted outside of the sump. External skimmers also include hang-on ones which hang on the edge of the tank.
Internal Sump P. S | External P. S |
---|---|
1. Less space required | 1. More space required |
2. Less expensive | 2. Can be expensive |
3. Efficient in cleaning waste | 3. Equally efficient |
4. Requires sump | 4. Can be installed to any tank |
5. Leaks are contained | 5. Leaks can be problematic |
6. Submerged and will wear over time | 6. Lasts longer |
Choosing The Right Protein Skimmer.
There are many factors to consider when choosing the right protein skimmer for your seahorse aquarium. These factors include tank size, bioload, space required, and the type of skimmer you want.
Tank Size – Protein skimmers come with a manufacturer’s recommendation according to tank size and volume of water.
However, because seahorses require extra power for cleaning, it’s advised to get a skimmer twice the one rated for your tank.
For example, if you have a 30-gallon tank it’s best to get a skimmer that is rated for a 60-gallon tank.
Bioload – Bioload refers to all the waste that is produced inside an aquarium. Seahorses have quite a heavy bioload even if you just keeping a pair.
Their messy feeding habits and waste expulsion can quickly cause water quality to decline if left unattended.
Because of this heavy bioload, it’s best to choose a skimmer twice the rating just as mentioned above.
Space – Space plays a significant role when looking for the right skimmer since you don’t want to have your tank cluttered.
If space is limited you want to get a skimmer that is small enough to fit or you can get an internal skimmer that won’t require much space.
Type – There are a few types of skimmers to choose from, internal sump skimmers or external skimmers. Depending on your aquarium setup you can choose one to fit accordingly.
Normally hobbyists start off with a single-pump internal protein skimmer since it’s affordable and easy to install.
In the case of more advanced aquariums then you would need a more powerful skimmer that will be ideal for the tank’s capacity and the bioload.
The Best Protein Skimmers.
1. For Aquariums 30-60 gallons.

The AQUAMAXX BULLET-3 HANG-ON-BACK PROTEIN SKIMMER is one of the best for smaller tanks under 60 gallons.
AquaMaxx`s Bullet HOB Skimmer series was designed to deliver high performance in small spaces.
Unlike traditional hang-on-back skimmers which can be a large eyesore for your aquarium, the Bullet`s innovative bubble diffuser design allows for powerful filtration in a smaller footprint.
Comes packed with features such as an Innovative bubble diffuser design, ultra-silent operation, and a high-performance Sicce SHARK needle wheel pump.
Easy maintenance and cleaning, simple to set up and operate compact footprint, and durable cell-cast acrylic construction.
The Bullet-3 is the largest and best of the Bullet series, check out the latest prices here.
2. For Aquariums 60-90 gallons.

The AQUAMAXX CONES HOB HANG-ON-BACK PROTEIN SKIMMER is a great option for medium-sized aquariums ranging from 60-90 gallons.
The latest AquaMaxx ConeS HOB Hang-On-Back Protein Skimmer takes all of the great features of the ConeS CO-1 skimmer and adapts them to a hang-on-back version.
Now, you can get all the great performance of the ConeS CO-1 skimmer without needing a sump.
It is rated up to 175 gallons in a design compact enough to be placed on a small or medium-sized saltwater aquarium perfect for seahorses.
Check out the latest prices of the AQUAMAXX CONES HOB protein skimmer here.
3. For aquariums 90-120 gallons.

The AQUAMAXX CONES CO-2 IN-SUMP PROTEIN SKIMMER is designed for lightly stocked aquariums up to 300 gallons hence it will be perfect for seahorse tanks under 120 gallons.
AquaMaxx ConeS Series In-Sump Protein Skimmers efficiently remove organic waste from aquarium water.
The hybrid cone body, the advanced bubble chamber, and the proprietary conical diffusers work synergistically to efficiently mix air and water.
More importantly, random twirling and turbulent flow are eliminated.
A stable laminar flow is created inside the skimmer`s reaction chamber and maximizes the performance and efficiency of the skimmer like no other design!
Everything you need for an advanced seahorse tank, check out the latest prices here.
4. For Aquariums 120-150 gallons.

The AQUAMAXX CONES CO-3 IN-SUMP PROTEIN SKIMMER is an ideal advanced filtration mechanism perfect for those larger tanks.
Similar to the AquaMaxx Cones CO-2 but with greater performance power for heavy bioload of larger tanks.
AquaMaxx ConeS Series In-Sump Protein Skimmers efficiently remove organic waste from aquarium water. The hybrid cone body, the advanced bubble chamber, and the proprietary conical diffusers work synergistically to efficiently mix air and water.
Features include.
- Modified and upgraded Italian Sicce needle-wheel pump produces optimum bubble size for high-efficiency protein skimming
- Efficient, durable, and reliable
- Simple to set up and operate
- Cell-cast acrylic construction
- ShockMaxx rubber feet isolate noise and reduce vibration
- Quick-Precise adjustment valve allows fast precision tuning of the skimmer water level to control wet/dry foam production
- Exclusive collection cup design with a handle that allows you to easily hold and transport the collection cup for cleaning
An all-around great product powerful enough to meet the demands of a thriving seahorse aquarium, find the AQUAMAXX CONES CO-3 IN-SUMP PROTEIN SKIMMER conveniently on aquarium specialty.
The Best Biological Filtration For Seahorses.
Unlike other filtration systems, biological filtration uses living organisms to remove harmful substances from the water.
Biological filtration is the action of bacteria in the tank breaking down dangerous ammonia, converting them to nitrites, and then the nitrites to the less toxic nitrates.
This process is known as the nitrogen cycle and is important in a saltwater aquarium hence cycling is required.
Biological filtration has many benefits, it reduces ammonia spikes, provides stability within a tank and it helps reduce maintenance.
The best type of biological filtration for a seahorse tank include
1. Cured Live Rock.
Live rocks are rocks taken from the ocean and introduced to an aquarium. Even though the use of live rock is completely optional it has many benefits.
Live rock is a great way to add beneficial bacteria to a seahorse tank. The benefits of live rock include increased stability and denitrification to keep the nitrate levels nice and low.
In fact, most hobbyists use live rock as the primary means of biological filtration.
However, there are certain risks that come with keeping live rock like introducing pests and other hitchhikers to your aquarium.
For this reason, live rock must be properly treated so all unwanted pests are removed before the rock is introduced to a new tank.
2. Substrate Bottom.
A substrate bottom refers to a layer of sand (1-2 inches) at the bottom of a tank.
This provides surface area for beneficial bacteria to grow, increasing the biological filtration within an aquarium.
However, in a seahorse tank, you must choose the right substrate that will be suitable for their needs as well as the needs of their tankmates
3. Ceramic Media.
Ceramic media are porous structures that provide a lot of surface area to house beneficial bacteria.
These are great for developing good biological filtration within your ecosystem and they are easy to use.
There are many types of biofilters, but the recommended ones include
- Ceramic rings.
- Ceramic Balls.
The Best Chemical Filtration For Seahorses.
Chemical filtration refers to the use of aquarium-safe chemicals to remove contaminants from the water.
These chemicals normally remove dissolved organics from the water changing the chemical composition of the water.
There are two main types of chemical filtration that are used in saltwater aquariums. These are activated carbon and GFO.
Activated Carbon
Activated carbon is made from various base materials that are highly porous. When this substance comes into contact with water the carbon absorbs the wastes from the water as well as any unwanted color and odors.
There are many activated carbon products that you can use but we recommend Premium Activated Carbon.
GFO (Granular Ferric Oxide)
Granular Ferric Oxide is a safe and effective way to get rid of phosphates and silicates from the water.
This type of filter media works by the process of absorption where phosphates and other chemicals adhere to the media hence cleaning the water.
We recommend GFO HC by KOLAR LABS which is a very safe and effective phosphate-reducing agent.
The Best Clean-up Crew For A Seahorse Tank.
Although a clean-up crew isn’t really considered filtration I believe it plays an important part in the maintenance that is required for a seahorse-specific tank.
Clean-up crews normally consist of an assorted group of invertebrates working together to feed on the excess food and waste that settles on the bottom of a tank.
These crew members play an important role in reducing detritus build-up and ensuring overall water stability.
When looking for a good clean-up crew for seahorses you must strategically choose tankmates that are compatible and who won’t outcompete them for resources.
The most common crew members for a seahorse aquarium include
- Nassarius Snails
- Trochus Snails
- Astrea Snails
- Scarlet Reef Micro Hermit Crabs
- Micro Brittle Starfish
Final Thoughts.
Filtration is one of the most important mechanisms in ensuring safe water parameters in a seahorse tank.
Although it’s not a one size fits all kind of thing it definitely requires a good variation of filter mediums for best results.
Combining mechanical, biological, and chemical filtration will be essential for forming a fully structured filtration system powerful enough to combat the messy tendencies of seahorses.
A great addition is a compatible clean-up crew that will work in conjunction with the filtration system to make sure waste is at its minimum.