gUSH Orb CO2 indicator review


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Nathan Hill takes a look at a new piece of aquarium glassware from gUSH.

I’m seeing lots of unusually-shaped drop checkers. Some, in white plastic, seem to last mere seconds before getting smothered in green. Others are too curvy for my tastes, hooking over the tank like some glass bathers at a swimming pool.

If, like me, you prefer things more minimalist, you’ll enjoy the Orb indicator from gUSH.

There’s no hidden trick or unique selling point, other than the shape.

It does what other drop checkers do. You fill it with your indicating 4°KH solution (not supplied), place it into the tank and away you go.

I had a pleasant surprise when I cleaned it for the first time. I gave it a once over with an old scouring pad and no sooner had I wiped than all the writing came off. If you want to retain the name labelling on it, use a soft cloth.

Otherwise, you can make it even more minimal by giving it a quick wipe with an algae pad.


This seems sturdier than its fancier counterparts. I get through lots of glassware with my big, clumsy fingers, but I’m confident that it’ll take more than just a little heavy-handed knock to break this one…

Price: £14.50, from

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