1B Baffle Tub – Aquarium Sump

1B Baffle Tub – Aquarium Sump Details

SKU: seamless-sump-1b Category:


The Seamless Sump® Baffle Tub is designed to provide three critical functions of any sump filtration system for a large aquarium. The left side of the baffle holds our bio media baskets. The right side of the baffle is designed to function as a return pump chamber. The right side has a cord grommet and two holes for the your return lines.

This includes: 5 Media baskets, 5 liters Bio media, and a 10 PPI foam pad w/ perforated aluminum basket divider.
You can add an additional media basket to make your bio media filter a wet-dry system.
Do you want to have bulkheads added for plumbing lines to another tub.
Product total
Options total
Grand total

Height 17 in
Length 20.75 in
Depth 17 in

High Density Polyethylene (HDPE)

Max Volume

18.6 Gallons

Ideal Operating Volume

14.3 Gallons


The Seamless Sump® Baffle Tub is yet another innovation from Custom Aquariums. The Baffle Tub provides a place for both bio media and return pumps.

The media baskets provide organized, high volume, efficient, high surface area for bacteria culture. This in turn provides the best resulting biological filtration. It is easily to organize and rotate media baskets, so you can provide a consistent fresh supply of bio media to the culture. There is an optional pad on top of media stack that prevents debris and refuse from getting into your media stack.

The baffle design prevents debris and micro bubbles from getting to the pump side of the tub. The baffle design also ensures the media stack is always submerged in water even if the water level goes down on right side of the tub due to evaporation.

The tub comes standard with cord management grommet to easily connect your pumps, heaters, and other in sump equipment. It also comes with two holes for your pump’s return lines to the aquarium. The rectangular water inlet on the left side is molded to couple to one of our sock tubs or our new Skimmer Tub.

The Seamless Sump® Advantage

Every Seamless Sump® tub is made out of a single molded piece of durable high density polyethylene (HDPE). Our filtration tubs are easy to clean. It has no seams, no welds, no leaks.

You can mix and match our tubs in different combinations to create the perfect filtration system for your aquarium’s needs. The number of combinations and possibilities are almost endless!

Baffle Tub

Seamless Sump® Baffle Tub Key Features

  • Most innovative, patent pending baffle design on the market!
  • One piece molded baffle design – no seams, no welds, no leaks!
  • Media baskets provide organized, high volume, high surface area, efficient bacteria culture for biological filtration
  • Easily organize and rotate media baskets providing a consistent, fresh supply of bio media to the culture
  • Optional pad on top of media stack prevents debris and refuse from getting into your media stack
  • Unique Baffle design prevents debris and micro bubbles from getting to the pump side of the tank
  • Baffle design ensures media stack always submerged in water even if water levels go down on right side due to evaporation
  • Not under pressure – no reliance on seals that can fail over time
  • Redundant pumps – in the event of a failure replace an inexpensive pump rather than an entire filter
  • Use with Siphon Stopper® to drastically reduce likelihood of back siphoning
  • Comes standard with cord management grommet to easily connect your pumps, heaters, and other in sump equipment
  • Standard 1-1/2” molded in slip fitting over media stack to easily connect to your overflow
  • Made from one piece molded HDPE sump material, which is far superior to acrylic or glass for this use
  • Fits most commercially available stands through the front!
  • Many ways to configure to meet your needs

Unique Baffle Design

Baffle design ensures the media stack on the left stays submerged in water. This facilitates efficient filtration and prevents odor.

The right half acts as an isolated pump housing and as an evaporation reserve where the water gets returned back to the tank through the pumps. You can also put your heaters in this half so you don’t have to look at it in your aquarium, and easily run the cords out of the top cord management grommet.

Additional reservoir tanks can be connected to the right side of the tank to allow additional evaporating capacity or refugium capacity.

You will never see an evaporation water line on the top of your aquarium, all of the evaporation takes place in the right half of the baffle tub and the reservoir tub.

Wet/Dry Configuration

An additional basket can be added to the stack. This basket will be entirely out of the water, making an easy wet/dry configuration. See below for more details.

Baffle Tub Design

Seamless Sump® Baffle Tub

The patent pending Seamless Sump® baffle tub is a truly ingenious innovation. Through our vast experience servicing aquariums (Serenity USA) our full time professional service technicians and engineers took the best features of canister and sump filtration methods, engineered around the flaws, and combined them into one simple, elegant, “Seamless” solution.

Organized Media Stack

The media stack on the left side of the baffle creates a very organized, high volume, high surface area, “good” bacteria culture. The water efficiently pours through the bio media in the basket stack (recommended with our glass bio ball filter media) to balance the water and makes its way to the other side free of debris and micro bubbles. The baskets facilitate easily rotating the stack with fresh bio media without any guesswork as to what is fresh and what is old (as opposed to other systems where you just randomly throw the media in the bottom of the tub). The baskets also make it easy to add micro filtration pads as well as purigen or carbon bags to further polish and purify the water.

Baffle Tub Media Stack

Seamless Sump® Wet/Dry Filter Options

Media Stack Versatility

Add another basket to the top of the media stack and instantly convert your seamless sump® to a wet/dry filtration sump.

A wet/dry filter is when you have part of your media stack non submerged and exposed to air.

Studies have shown this wet/dry configuraiton of water cascading over bio media culture that is not fully submerged in water will accelerate the aeration proccess and help the good bacteria more efficiently process the nitrates in your tank.

The downside, however, is you may experience odor if your wet/dry basket isn’t serviced regularly because particles from this bacteria can more easily evaporate into the air you breath. This is why most people choose to opt out of the wet/dry optional basket and leave the entire stack submerged in water. You may also experience a slightly higher rate of evaporation in your setup.

Our configurations tend to have a lot of aeration and filter media already without the need for wet/dry filtration, however this is a customer preference we can easily accommodate either way, all you have to do to turn your regular baffle tub into a wet/dry baffle tub is order an additional basket and fill it with media.

Wet/Dry Option

Just add a basket to the top of the stack and you instantly have a wet/dry filter.

Wet Dry Baffle Tub

Filter Pad and Carbon/Purigen Options

More Media Stack Options

Pre-cut filter pads are available and can be placed anywhere inside the media stack (usually on top for easy cleaning). The filter pad isn’t usually necessary if you are incorporating a filter sock tub. However, if you are not using a filter sock tub the filter pad is highly recommended to prevent debris from entering your media stack.

Purigen and/or activated carbon bags can also be placed anywhere in the media stack to further purify your water. Either solution will help remove nitrates and other impurities from your water.

StuPurigen is a synthetic carbon that can be re-charged and re-used. We use Purigen in all of our service aquariums for this reason. To re-charge, just soak in a mild bleach solution, rinse thoroughly and it will last for several water changes. We use and sell our Purigen in reusable bags as to limit the overall long term operational costs. Once the Purigen no longer re-charges, simply cut the bag, empty the old Purigen, and replace with new. The bags seal with any plastic bag food saver type sealer. Over the long run this will save you money and give better results.

Layered Baskets

Baskets come with ribs half way up to support a perforated divider plate that allows you to add things like alternative media, foam pads, Purigen/carbon, etc. to any basket.

Baffle Tub Media Stock Options

One Piece Molded Design

The one piece HDPE (read more on HDPE) design ensures no welds, and no leaks. The unique baffle design ensures the media stack is always covered in water at a given height regardless of evaporation levels. The baffle also ensures micro bubbles do not enter the pump side of the tub and re-enter your tank, as well as prevents particles from getting to the pumps which could limit their life.

Not Under Pressure, No High Stress Leaky Seals

The fact this entire system is gravity fed and not under pressure means you have no seals under high pressure stress that will inevitably fail over time and cause a leak or flood. This is a critical advantage the Seamless Sump® system has over canister filtration. You will not find any “gasket replacement kits” for sale here, because there aren’t any needed for our system.

Built for Redundancy, Low Lifetime Operating Costs, and Safety

Unlike other manufacturers we design our equipment to last a lifetime®, not just to sell you consumable parts or expensive replacement components. With our sump system, if a pump fails over long periods of time simply replace the pump without having to replace the entire filter (as with canister filters and many other designs). Our recommended setups have two pumps, so in the event of a pump failure you are still have safe levels of water flow while you replace the wore out pump. Used in conjunction with the Siphon Stopper® back siphoning during a power failure is not nearly as likely as compared to relying on failure prone check valves or worrying about leaky canister filter gaskets.

Unmatched Versatility

Baffle tub comes standard with a cord management grommet to easily get the cords out of your tub to connect your pumps, heaters, and other in-sump equipment without leaving a gaping hole for evaporation. Also comes with a molded in 1-1/2” slip connection on top of the bio media stack to easily connect to your overflow. All tubs come with a multitude of molded dimples that can act as pilot holes for custom fabrication. This allows hobbyists to drill their own tubs as they see fit and easily maintain consistent height and spacing. This facilitates even water flow as well as a professional, clean appearance even if you are fabricating it yourself. The possibilities are endless with the ways you can build different configurations for different needs. Give us a call, one of our service experts can help you design an ideal filtration system for practically any size or style aquarium.