alexk3954 - I'm thrilled that you are drawing some inspiration from my little tank. It's a ghetto system compared to many (if not most) here on RC, but if it speaks to you, then roll with it. I'm also glad you find this thread instructive. Thanks again to the group of experienced reefers out there (Melev, John, Bax, et al) who continue to offer their words of wisdom and encouragement to me. Remember, I'm still a newbie myself!
As John implied, bryopsis, flatworms and other pests are considered undesirable hitchhikers. We all celebrate when we find an unexpected coral on a piece of rock or a cool crab that crawls out of a coral colony, like an acro crab. These would be considered "desirable" hitchhikers. Sometimes, on the other hand, there may be undesirable hitchhikers that we don't see when we acquire a new specimen, like maybe a mantis shrimp, redbugs, or ... flatworms. In my case, I've had my share of favorable hitchhikers, like some zoos that have appeared out of nowhere and tiny corals that I'm trying to preserve to see what they'll develop into. Of course we have to take the good with the bad. I don't know exactly where the bryopsis came from that's in my tank - likely from the live rock. I am, however, quite certain where I got the flatworms. It occurred when I purchased my blastomussa colony from my LFS. I saw a relatively large (about 2 mm) gray worm crawling around in the bag while I was acclimating the coral, but not being sure what it was I placed the colony into my tank anyway. A few days later I began seeing baby-sized gray worms along the glass, and their numbers increased daily. This illustrates the importance of quarantine! Granted, I don't quarantine corals, but I dip them and I should quarantine. At least now I know what to look for, but even then it's not foolproof, as some of these pests are difficult to see. Take the acro-eating flatworms, for example. These can be quite difficult to see, and may go unnoticed until the corals are literally being eaten away. It's a small investment to set up a quarantine tank - clearly cheaper than the time and money necessary to eradicate an infestation. If I'd total the dollars I've spent on Flatworm eXit, PraziPro, carbon, salt (for increased water changes), mesh bags, etc., not to mention the number of hours involved in performing the treatments, I could have easily bought a nice light fixture and maybe even a small HOB skimmer for a QT and could have avoided contaminating my tank in the first place. The bryopsis would have been tougher for me to avoid, as it was probably dormant in my LR for a few months before blossoming out. But I've been battling this stuff just as tenaciously, with manual labor (pruning), attempting to achieve optimal water quality/chemistry, and adding natural predators like lettuce nudis. Sure, this hobby has its frustrations and challenges, but that makes it all the more exciting, for me anyway.
I don't have a picture of the flatworms, primarily because the camera I use (it's my wife's camera) is an old Nikon CoolPix 990 and the macro function isn't very good. Flatworms come in different colors; the red ones (planaria) are more deleterious than the gray ones that I have. They look like tiny arrows, 1-2 mm long, with a bifurcated tail.
Amazingly I don't have a good picture of bryopsis. I should have taken a full tank shot when the stuff was in full bloom and all over my tank, but I guess I found it too disgusting. If you look back one page at the photo of my stomatella snail, you can see a small tuft of it along the glass. Also, check out this older full tank shot - I had just pruned before taking this photo but there's a fairly nice tuft of bryopsis at the bottom left corner of the image, and some more immediately beneath the red monti cap, just to the left of the frogspawn sitting on the substrate.
John - Hmm, not sure if another lawnmower blenny is going to be the fish for me. I'd hate to starve another one to death, and the wife wasn't so keen on its looks. I thought it was quite handsome. With only enough property in my tank for 4 tennants, I have to be pretty selective about who I'll rent space to. Maybe I need some more suggestions. The goby is a good option and the small size doesn't deter me. Even if it doesn't wipe out the algae, that would at least ensure a constant food source.
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