Clscea U-Shaped S Mini Acrylic CO2 Diffuser with Check Valve

The Clscea U-Shaped S (part B7726) is a mini CO2 diffuser for small aquariums. It is made of acrylic, which is clear like glass but not fragile, and uses a fine ceramic disc to break CO2 into small bubbles. A check valve comes in the box.

Why the U shape

The U-shaped body lets the CO2 line enter from above and turn up into the diffuser head. That keeps the tubing tight against the glass and makes the unit easy to tuck behind plants or hardscape in a nano tank, where a large diffuser would stand out.

Acrylic instead of glass

Glass diffusers can crack when you press a suction cup on or clean them. Acrylic tolerates handling better. It can scratch, so clean it with a soft brush rather than an abrasive pad.

Setting it up

• Fit the included check valve on the CO2 line outside the tank, so water cannot run back into the regulator.
• Place the diffuser low in the tank, near filter outflow if possible, so bubbles travel further and dissolve.
• Start with a slow bubble rate and raise it gradually over several days.

Bubble size

New ceramic discs often release larger bubbles at first and get finer after soaking. If the disc stops releasing gas, Clscea asks buyers to contact the seller for help with correct setup before assuming a fault.

Cleaning the disc

Algae and biofilm slowly block the ceramic pores. When the bubbles get larger or the rate drops, remove the diffuser and soak the disc in a diluted bleach or hydrogen peroxide solution, rinse thoroughly, then put it back.

Choosing a size

This is the small version, aimed at small tanks. For a larger tank or a model with a bubble counter, compare the FZONE acrylic diffuser or the FZONE Neo.

Use a drop checker alongside it to judge the CO2 level in the water, since bubble rate alone does not show how much is dissolving.