
The Stealthbox® is an innovative addition to the H2Overflow®, bringing enhanced versatility and sound reduction to the aquarium overflow system!
Watch our overview video or learn about all the benefits below!
Benefits of the H2Overflow® and Stealthbox®
The H2Overflow® skimming screen is an excellent addition to any sump filter, with various benefits such as:
- Usable on almost any sump filtration system.
- Offers maximum surface area with a minimal footprint.
- Up to 1200 GPH of water flow with one overflow.
- Use multiple overflows at once to increase turnover.
- Installs out of sight and hides water lines.
- Attaches to holes drilled at the top to minimize flood risk.
The Stealthbox® adds even more benefits to this overflow system:
- The top of the Stealthbox® rests at the top of the tank, eliminating water lines below the upper rim.
- Accommodates up to three H2Overflow® screens (3600 GPH).
- Made of the industry’s strongest black PVC in a one-piece, molded unit.
- No welds that can crack or leak.
- The PVC cover reduces the noise caused by the overflow.
- Designed with various slip fittings inside and outside of the overflow box.



Stealthbox® Key Features
- Many internal plumbing configurations.
- Four molded-in 1–1/2” slip fittings, three 3/4” slip fittings, and three 1/2” slip fittings on the bottom inside and outside of the box.
- Comes standard with two 1–1/2” slip fittings open and ready to use. The remaining fittings have pilot hole dimples ready to drill.
- Internal plumbing kits and ball valves are available.
- Can be a completely gravity-fed filtration with no external sump needed.
- Just as effective as a canister filter with less leak risk and easier maintenance.
Stealthbox® Internal Plumbing
The H2Overflow® Stealthbox® can be configured in many ways. We offer some suggestions below, but with our ultimate kits, you can experiment with several overflow setups. Please contact us with any questions about setting up an H2Overflow® Stealthbox®!

Configuration 1 – up to 3600 GPH
Our most popular configuration with a large system that has a protein skimmer involved. Position 10 you can manipulate with the ball valve to have just the right amount of water go into your skimmer, position 7 would take on 99% of the remaining water. You would open the vent to start the siphon, then close the vent to create a full siphon eliminating noise. Position 4 is to take on the remaining 1% of the water. This position 4 trickle is so small, the water sticks to the side of the pipe it makes virtually no noise. It also has a lot of excess capacity in case position 7 siphon gets interrupted. You would leave the vent off on position 4 to make sure a siphon is not necessary if position 7 gets clogged. Position 1 is a backup to the backup, a fail-safe to make sure absolutely no problem with any of the other outputs results in an incident. This also works great with 4 sock tubs.
Configuration 2 – up to 2400 GPH
This is a popular configuration for a double sock tub with backup emergency redundancy. Position 7 is used to take on 99% of the water which can be accomplished by manipulating the ball valve. Position 4 is intended to take on the remaining 1% of the water and has enough excess capacity to take on more if position 7 loses its siphon. Position 1 is a backup to a backup for extra redundancy. This can be hooked up to a quad sock tub, or a double sock and teed to a baffle tub, or a reservoir tub that is in line with a pump chamber so long as the reservoir is plumbed to the pump chamber with at least 1-1/2” tubing.


Configuration 3 – up to 2400 GPH
This aquarium overflow configuration is a way to more evenly distribute water to 2 different socks where backup redundancy is not needed. Can be done with or without the elbows. If elbows are used, we recommend not attaching the vent to at least one, and only have 1200 GPH per open vent. (If both vents open, 2400 GPH, one vent closed, 1200 GPH, never close both vents).
Configuration 4 – up to 2400 GPH
Same as configuration 3, but without the elbows. A very simple, elegant solution with more control than a single ball valve.


Configuration 5 – up to 3600 GPH
This is a very simple, safe solution for aquariums all the way up to 3600 GPH. By not using the 180-degree elbows, you eliminate all the risk involved with any kind of siphon. Just use the ball valves to manipulate water drainage until you hear no noise. Use up to 2 of the outputs merely as backups! A very popular fish tank overflow solution.
Again, these are just a few suggested uses. Let us know what else you come up with, we would love to share even more ideas with our online community! Email photos and ideas to [email protected]!
Stealthbox® Components



With 10 molded fittings, there are many possible orientations, making the Stealthbox® the most versatile overflow and the perfect rear-hanging system for the do-it-yourselfer.
Please contact us if you have questions about the product or its best uses. For more information on setting up an H2Overflow® Stealthbox®, watch the instructional video below!