I try to encourage sponge growth in my tank because I quite like them and are also fascinated by them, however there's one particular sponge that's been giving me cause for concern recently. It hitchhiked into the tank on the shell of the large thorny oyster 9 months ago. When it first arrived it was a tiny white blob but as time has gone by it's turned grey and grown bigger. By the end of January 2022 it had completely obscured (killed?) the purple tunicate that had been growing behind it and was spreading over the thorny oyster shell as well as in front of the right side of the Frond oyster. I was beginning to wonder about the identity of this sponge, could it be the dreaded chicken liver sponge? Apparently chicken liver sponge can be invasive, growing over/killing corals and it should be removed as soon as seen. This is what the sponge looked like as of last week. I scoured my books and the internet for information on grey sponges and came across Chondrosia reniformis (aka kidney sponge). This species can be mottled brown to grey in colour *check*. Grows into smooth, irregular kidney-shaped encrustations, *also check*. What particularly caught my eye though is that colouration depends on light intensity, the brighter the illumination the darker the sponge and that is exactly what I have seen with this one. It started off white and over time has turned dark grey. I assume in the wild the sponge/Thorny oyster came from a shaded location and now in my tank is pretty much under full lighting. There is a similar species named Chondrilla nucula (chicken liver sponge, uh oh!) which is also a possibility but I'm leaning more towards the first species at this point.
I'm quite fond of bivalves as well as sponges, if things continued as they were the sponge would probably grow over the Frond oyster preventing it from feeding most likely resulting in its demise. Given the choice between the two I'd rather keep the former and loose the latter. Also if this sponge really is invasive then much more would be at stake eventually. C. reniformis is described as leathery and uses collagen fibres for support instead of calcareous spicules etc so I rather naively assumed that I could simply peel it off the shell. I tried this with a pair of tweezers but all I did was puncture the sponge in several places causing the release of some unknown grey liquid. Clearly removal was not going to be quite so simple. Also the following day I noticed that the coralline algae growing in the vicinity of the sponge was now dying off. Coincidence? I think not! Some sponges are said to be toxic to keep from being eaten so perhaps this was one of those. Also the sponge seemed not to be bothered by multiple stabbings with a pointy pair of tweezers. Plan B was to perform surgery outside of the tank in case there was a chance of any more toxins being released. I detached the spiral coral, no point in risking that too, and moved the oyster shell over to a bowl containing some tank water. I then proceeded to pick off the sponge bit by bit, when most of it was gone I scrubbed the entire area with a stiff brush. After rinsing off with some additional saltwater I plopped the shell back into the tank and crossed my fingers. A quick check with the magnifying glass did show some tiny bits of sponge still remaining on the shell, hopefully they will die off in a couple of days. The Frond oyster survived the scrubbing ordeal and was opening up again not long after being back in the tank, the Jewel Box clam however took a couple more days to feel comfortable again. It seems to be fine now thankfully. I am yet to see the feather duster reemerge, I hope I didn't squash its tube. Fingers crossed I have dealt with the sponge, either that or I've spread it around the tank. Eeek!
0 Comments
...and hopefully I can keep celebrating it for many years to come.
Back in November a couple of days before my birthday I spotted something awesome for sale online. Something I have always wanted to keep, my holy grail of livestock so to speak. A series of messages passed back and forth between myself and the shop. First I checked the size, then I checked price and then I checked if it was still available. I didn't think I had any space left in the tank but where there's a will there's a way right! My lovely husband said "birthday present, let's go!' So we did and once I saw the item in question I knew I couldn't leave the shop without it. I traded in some zoanthids in order to make room, well, who needs zoas anyway?! So that's how Christmas arrived for me in November, a Christmas tree worm rock! In addition to the worms and the Cyphastrea coral host, there is also one really Hench Vermatid snail (I can hear many reefers screaming right now), lots of teeny tiny barnacles, a rather gorgeous Tunicate and four super awesome Paguritta crabs. At the time of writing this post (I'm behind on my updates once again) the rock has been with me for just over two months. I lost a couple of the worms early on (during week 3 & week 5), they were both close to each other so I hope they were already doomed rather than unhappy with my tank conditions/feeding. I haven't lost any more since then, there are at least 35 worms remaining. The host coral appears to be doing really well so far. To begin with it was quite brown but has since turned a lovely shade of fluorescent green it's also spreading over the bare parts of the rock too, I'm extremely happy about that. Articles online say that if the host coral dies then the worms will too, I don't know about that but I'd rather not have to find out. Needless to say I've taken a LOT of photos of the life on this rock, everything about it fascinates me. I'm not going to post them all in this post but they can be found on the livestock page (click here.) I love getting out the magnifying glass and looking at the small stuff, there's always something new and cool to discover. |
AuthorHi, my name is Lisa and I live in Derby, UK. I am a self-confessed reefaholic! Archives
July 2022
Categories
All
|