[asylumdown]

Considering my recent tank drama y'all are going to think I'm nuts for doing this, but cyano has been getting crazy AGAIN. I'm doing daily water changes and I *think* things are starting to turn around (I'm seeing hints of new growth plates at the edges of where things have died), but just like last time, the cyano is threatening to de-rail any recovery by directly killing corals.

I'm officially off the chemiclean train, so I've been looking for other ways to control cyano. I came across thread after thread of people dosing their tanks with hydrogen peroxide. I did a whoooooooooooole bunch of research, and there's actually a whole bunch of scientific research supporting peroxide as a good agent of cyano control with relatively few side effects on other plants and critters.

I'm not gonna do anything drastic until my tank is WELL more along in it's recovery, nor am I ever gonna dump an oxidizer in my tank every day, but just to test if I could use it as a spot treatment for cyano at some future date, I whipped out a 1ml syringe with a needle point tip from an old red sea calcium titration kit and the bottle of 3% hydrogen peroxide I had to buy to clean the stitches I got after impaling myself with scissors the night HWYman came over (dude, once again, that was the most embarrassing thing that's ever happened to me. Right up there with gluing my lips shut when LastLight was here). I picked a little prominence of rock and the remaining nub of dead skeleton of a coral that died in the first wave that I couldn't get off the rocks (that is the first place cyano shows up it seems). Total area of about 20cm square total.

I turned off all pumps, waited until the water was perfectly still, and squirted the peroxide very, very slowly over the cyano patch. I used a total of 6mL of hydrogen peroxide (0.016mL/gallon), and waited half an hour before turning the pumps back on. The cyano bubbled like mad the whole time the pumps were off. During this time, a turbo snail motored by with no ill effect, though a bristle worm that was in a crevice I injected directly crawled out and did a death dance.

I turned the pumps on around 4pm. As soon as the current hit the rock, a cloud of red pigment was blown in to the water. 3.5 hours later, 99% of the cyano in the places I treated is gone. I'm not going any further until I'm sure my tank is getting better, but it's nice to know this option is available and appears fool proof

If someone is looking at the early stages of a cyano problem and is considering chemiclean, I might suggest trying spot treatments with very small amounts of hydrogen peroxide first. Chemiclean is a system wide anti-biotic with unknown ingredients, while hydrogen peroxide, if dosed in small enough quantities relative to the system, will have little to no system wide effect impact and rapidly breaks down in to oxygen and water. It also has a small mountain of published scientific research behind it showing that is both effective against cyano, and relatively harmless (at concentrations hobbyists would achieve) to eukaryotic cells.