How I got rid of red slime


Active Member
I have seen many posts about red slime or cyano-bacteria in people's tanks... here's my story.
I used to have a very bad red slime problem in my tank. It literally covered everything... I scrubbed the rocks in a separate bucket and did a water change (100%) only to have it come back in full force within a week.
Everything looked fine. My nitrates, ammonia and nitrites were all 0ppm. My pH stayed at 8.3, my SG was at 1.024, my temp stayed at 81 and my alk read "high". I replaced my lights hoping they may be the problem but to no avail... I'm running 325 watts of PC lighting on my 72gal tank. I have 2 maxijet power heads and have angled them along with the main water line to keep the water moving with few if any dead spots. Water flow was not a problem because I would even have red slime growing directly in the jet of the powerhead.
I run ozone, and over sized skimmer that constantly produces lots of junk and a UV sterilizer. I do not dose anything in my tank but keep the parameters in check with water changes. I use RO water and Oceanic salt. Thinking my RO filter might be old I replaced it... to no avail.
I scrubbed and scrubbed and it kept coming back. One day I finally dosed with a bottle of "anti-red" but nothing happened. I lost the directions and found that I hadn't done it correctly. I was still running ozone and UV and I had carbon in the tank... all no nos.
So then I took everything out of the tank. EVERYTHING. I now had just a bare bottom and some fish. I put everything in quarantine in near total darkness for 2 months with nothing but water changes and a powerhead to stir the water. I put everything in a couple of clean trashcans. At this point I didn't care about killing my LR, I just wanted the red slime gone. In a bare bottom tank with nothing but fish, all parameters still being perfect, the red algae started coming back! I kept cleaning my filters and emptying my cup and scrubbing the tank but it would not go away. I cut back on lighting severely but it was still there...
Here's how I got rid of it... After putting everything in quarantine for months I pulled a few rocks out to test them in the main tank. I cleaned the tank and the rocks and within a few days of being back in the tank the red slime started growing on the rocks again. So this time I cleaned the tank one last time and put everything back in... The rocks, substrate, everything... I cleaned everything well before I put it in and made sure that all the filters were clean. Then I followed the directions on the anti-red bottle...
With the tank CLEAN, I turned off the ozone, UV and removed the carbon. Then I mixed the bottle in a gallon jug of RO water and added half of it to a high flow area of my tank. Within minutes the entire tank was looking red and hazy but my fish did not seem to notice. My skimmer immediately started spilling out red liquid and so I turned it down so that the anti-red would not get skimmed out of the water so soon. I waited 6 hours (longer than the bottle recommends) and then added the other half of the treatment. I had to empty the cup several times. Success! The red slime did not come back and I have noticed no effect on any of my fish, inverts or plants. It has now been almost 3 months and there is still no trace of red slime in my tank! All water checks showed good parameters. I did not see any change in nitrates or anything else. Everything stayed at 0 ppm so it did not crash my bio system...

my way

Active Member
One problem with your post, You did not say the name of the product used you simply called it anti-red. What is the name of the product?