Straight Glass Tube Rhinox CO2 Bubble Counter - Helps Maintain Safe and Healthy CO2 Levels for Plants & Fish - Includes Free Check Valve - For CO2 Diffuser, Live Aquarium Plant Aquascaping C02 System

This product did not come with any instructions and so I searched the web for more info. I found out that the smaller piece with the red glass inside is a check valve, allowing air through only in one direction. The check valve does not seem to work very well or I might be using it incorrectly. Most of these check valves has a way to tell which direction the air should be flowing, this one did not. I tested it by blowing into the valve.The bubble counter, although looks good, does not perform very well. You need to have the check valve connected to the bubble counter or the water will just flow down the air tube.All in all, I am not using this product any more. I went ahead a purchased a different bubble counter. The bubble counter does not seem accurate and the check valve does not work effectively. Don't waste your time or money on this bubble counter.

I was worried about ordering this item from reading the negative reviews and positive reviews that sound fake (sorry if they arent), but I did it anyway. Both the check valve and bubble counter are working perfectly fine, and are nice glass pieces that fit inline so they take up little space on the side of my tank and look neat. The check valve alone even works as a bubble counter if it is partially filled with water. I am using both with a DIY CO2 generator of citric acid and baking soda, and diffusing through a twig from my oak tree.

Both the original And replacement showed up broken.

Check valve let water drain back to my CO2 solenoid and the bubble counter is clumsy to use because you have to fill it with water and no matter which way you mount it there will always be a down side that is open that will let water out. There are better options available.

Bubble counter I received just drains the water or oil ect. Not like the other bubble counters I have used. I made it work by putting the check valve right below the bubble counter to "catch" the water trying to head down the tube toward my regulator. Overall not very impressed with this product

Works well. When I git it the check valve was broken. They replaced it. Haven't used the valve so I don't know how well it works, but I didn't buy it for the valve.

Bubble counter was smashed. Diffuser works great.

OK I just received the bubble counter along with the c02 diffuser, the diffuser is fine but the counter is broken, so if you get this item you should know that it's coming from Singapore, the actual counter is fine but the deal with the little red thingy in it... (I think it's a check valve of some sort) is the part that's broken... I can still use the counter however... It sucks that only half of it is usable...

This work superbly.It is a most for everyone.