I’m giving EasyCarbo a try
Mostly I think of “liquid carbon” as off-label algaecide. Since I’m struggling with green spot algae that made me wonder whether it was time to fresh up the liquid carbon approach and try something new…
For a while now I have been really struggling with green spot algae. This bad-boy clings to surfaces like crazy and has to be scraped off the sides of the aquarium at a minimum every two weeks using a plastic credit card blank. That works, but it’s hard work. The algae also challenges slow-growing plants by growing on the upper surfaces of the plant leaves, which makes the plants grow slower, so more algae can grow… It’s a problem.
There’s this concept of “liquid carbon” where instead of injecting CO2 into the water column (as I am doing) you add essentially a diluted version of some type of glutaraldehyde. Then there is a lot of voodoo-magic hand waving about what happens next… some claim the glutaraldehyde is metabolised by bacteria in the aquarium to CO2. Maybe that happens and maybe it doesn’t but it definitely doesn’t put enough CO2 into the water to move the colour of a drop checker, so probably that’s not happening to any meaningful degree. Then there’s some bit about “plant-absorbable precursor molecules” which again is probably simply wrong.
What there is relatively good agreement on though is that algae is pretty sensitive to glutaraldehyde, more sensitive than either fish or plants or shrimp or snails, so if you get the dosing right, you can poison the algae without poisoning the other aquarium inhabitants.
Sounds good and I think probably for real. For about a year now I’ve been working down a 500 ml bottle of Neutro CO2 which used to work (or so it seemed based on lack of algae) but which has progressively stopped working. The recommended daily dose for 40L of water is 0.9 ml, with advice that you can go up to twice as high for stubborn algae, but I’ve gone to 2.5 or 3.0 ml per day with no obviously detrimental effects on anything in the aquarium, including the algae. A few weeks ago during a water change I spread the Neutro CO2 in undiluted form on algae growing on the bubble tube and let that sit for 10 minutes or so. I figured that would kill it pretty good, but nothing happened. That got me to wondering whether the glutaraldehyde in the Neutro CO2 had “gone off” with time, part of the problem being that with a 500 ml bottle dosing 0.9 ml per day, that stuff needs to be stable for years.
So, I’ve picked up a small bottle of EasyCarbo and I’m trying that, 0.9 ml per day (same as the Neutro CO2 base dose) as the manufacturer suggests. I also tried putting some of the EasyCarbo neat on the algae in the bubble tube and I’ll report back in a few days as to whether that’s doing anything. I do like that the EasyCarbo comes in a 250 ml bottle so it doesn’t have to last as long, and the bottle is opaque brown plastic so if there’s any light sensitivity, that should be sorted out.
A boy can dream anyway…