10 gallon experiment in algae infestation....
This tank was donated to us by a math graduate student at UVM. When we got it, every object in the tank (including a bunch of shells, which were half-digested/dissolved where the algae was attached, a bunch of fake plants, a broken plastic ship, and other fine objects) were coated with a thick layer of forest-green whispy/furry slime. The gravel was covered with a blanket of the stuff. There was one Corydoras julii (very cute catfish) alive in the tank. The other inhabitants had died over the last while, and the owners were pretty discouraged. I transported the tank in the dead of winter, and was more concerned with the cory's health than with the algae problem, so I set up the tank without sterilizing it, to try to preserve the biological filter and not knock the cory's socks off.
When it seemed like the fish had adjusted, I bought two more cories, another C. julii, and one I can't identify (there are so many similar looking variants). Meanwhile, our convicts, in the 55 gallon tank, spawned (big surprise), and we moved the surviving 15 babies to this tank, after at least 75% of them had been chowed by tankmates. We figured they wouldn't bother the cories for a while, and we'd move them if they started living up to their reputation (of being territorial and aggressive). Mike and I went on vacation for three weeks, and when we got back, only five babies were still alive in the tank (for reasons described here). I sadly siphoned the carcasses out of the tank (Yuck!) and did some serious water changes.. Over the next few months, another convict and one of the cories died for mysterious reasons - I doubt it had anything to do with the algae, but who knows. They both looked perfectly healthy when I found them, except for the being dead part.
So, what of the algae? Well, I had never had an algae problem before (Bah! how I wish this was still true!), in any of my tanks (much to my pleco's dismay!!), so I was hoping the magical atmosphere and peer pressure from my other, algae-free tanks would intimidate the stuff out of existance.
As you may have guessed, I turned out to be [mostly] wrong.
Within a few weeks (I was on vacation visiting my family in England) of moving the tank, the algae was back full force, sliming every surface, including the mobs of water sprite and elodea I had thrown in before I went vacation. I added a pleco from another tank, and the furry glass became clear overnight. That pleco grew so fast in that tank (from 3" long to about 7" long in about a month!) that I actually sold him/her back to the petstore, fat and happy, because I didn't think I had enough tank space for more than one pleco.
I added a small Tiger Barb, which we got in a "buy three for...." kind of deal, when we bought some of the others for the 55 gallon tank. It was a good looking fish, but wasn't quite big enough, compared to the rest. We were afraid it would be picked on preferentially, and kept it in this tank until it bcecame big enough to join its buddies. It grew quickly, and is now living in a happy school of stripes..:) Once again, the cories seemed oblivious to the barb..
After the barb and convicts moved to the 55, I decided that I was sick of rubbing the slime off of the plants every week (I had decided that it was cyanobacteria, or "blue-green algae" by this time), and I was sick of the odd smell that the algae gave the tank, so I moved the cories to another tank for a while, and sterilized the tank and supporting apparati. I decided to test a theory, and sterilized everything by rinsing/soaking it with a mixture of isopropanol (rubbing alcohol) and water overnight. I have used the tank for other things since then, and I think this method killed all the algae. I had a small blue-green algae outbreak in the tank a few weeks ago, and I think it might have been from residual stuff that the alcohol didn't quite kill. Next time I'll use a spray bottle to get it into the cracks..
I like the idea of sterilizing with alcohol rather than bleach, because it kills things, but it doesn't require as much labor to rinse off the alcohol than the bleach, so it could potentially be done on a larger scale - it's easy to soak a 10 gallon tank in the bathtub overnight, but hauling a 55 gallon tank into the shower would be fairly risky, and dumping chlorine bleach solution on the lawn would be one of the dumbest thing I can think of doing. I am of the opinion now that it is still very important to rinse the tank thoroughly after treating with alcohol, to get off the junk you've killed or dislodged, but I think it's a safe and effective alternative to bleach.
Algae Infestation, Revisited!
Well, perhaps I didn't do a good enough job alcoholizing the tank, or perhaps my species of bluegreen algae is particularly insidious. It has returned full force. I allowed a carpet of duckweed and salvinia to blanket the tank surface, hoping I'd choke it out, but instead, the algae choked the plants out! Sigh. I'm thinking about resorting to antibiotics - although with my luck, I'll have gotten some strain that's resistant to the antibiotics I try. I wipe off the plants and apologize to them profusely every few days, but I'm not sure what the solution is. Perhaps I'll move the fish (several Aphyosemion bivitattum), two Otocinclus affinis and a Corydoras julii) to another tank, and subject it to evil experiments. Grumble!
Last Updated July 20, 1996
