These photos are from a couple of weeks back; since the weather has been hideous most of the time I have not been out much since. More practice with the m.zuiko 60mm macro lens abovewater. Above a small Strawberry anemone. Below a small Cushion star Asterina gibbosa and my finger tip for size. Below that the hydroid Candelabrum cocksii and an Idotoea isopod species (there are several common Idotoea species but I have not paid much attention to them yet I must admit). Finally, the adorable Worm pipefish Nerophis lumbriciformis which is common and usually found in small groups under rocks (I have never seen them underwater as they are small, slow, well-camouflaged and probably hidden most of the time). Definitely will try to get some more portraits of these lovely fish!
The weather has been generally awful so far this year and so I have not been out much. However it is March already so at least a small blog post is in order! There are loads of Worm pipefish Nerophis lumbriciformis around, some of the males carrying eggs (see also the blog header and the ‘about’ section). I found my smallest one yet. Next up a Sea urchin Psammechinus miliaris with what is probably the parasitic (or commensal?) polychaete worm Flabelligera affinis (thanks David Fenwick). After that, a slighlty out of focus shot of the hydroid Candelabrum cocksii. A few of these small individuals were sat under the first rock I turned over; I reckoned they were some type of spoon worm but they are something very different, thanks again David Fenwick, see for his much better photographs of this weird little thing here. Next the Wrinkled rock borer Hiatella arctica with siphon extended and the pretty acorn barnacle Balanus perforatus. Finally a picture of the Strawberry anemone Actinia fragacea, quite common and pretty, but I do not think I have ever posted a picture of it on the blog before. (All pics taken at Castle Beach in Falmouth btw.) I have three in my tank and it is high time for an aquarium update as well. I hope to go out tomorrow and the weekend as the tides are very low so watch this space!
A while back I wrote two posts on my personal top ten animals for the (unchilled) aquarium (here and here). Of course, there were also organisms that were not such a success. Animals can be unsuited for the aquarium for many reasons, and of course this depends on the size of aquarium, the combination of animals and what you define by ‘unsuited’; so please keep in mind that the following is a personal account!
Aggressive species: Another reasons that makes animals unsuitable for a community tank is that they are bullish. (Animals becoming too big is not a real problem for the native aquarium as you can release them again and replace with smaller individuals.) Crabs often get rowdy for instance. I kept a small (5 cm carapace width) Edible crab Cancer pagurus for a little while (his name was Barry). It would bury (Barry!) itself during the day, but as soon as the lights turned off it would go about and rearrange the tank. Rocks weighing over a kilo were knocked against the glass and I found a Cushion star cut in two. It was quite an operation to remove it from the tank using a net (but during all that rummaging I interestingly saw bioluminescence in the tank which was very cool). Shannies like to feed on snails and hermit crabs and so in a relatively small aquarium at least, so sometimes you have to choose between one or the other:
Truly littoral species: I had a couple of limpets Patella vulgata in the aquarium that just sat in the same place on the glass for months. At this time, algal growth was a problem, so I should have known if they had moved during the day or night by the tracks they would have made but they did not move a millimeter. The animals seemed a bit thinner in their shell, but seemingly they can survive for very long periods without food. Not being able to emerge from the water as they do normally seems to be a big problem for these animals.
Secretive species: Other animals simply are too shy or live underneath rocks; no point really in putting them in the aquarium if you cannot see them. This happened with Broad-clawed porcelain crabs, a Shore rockling and also a Shore clingfish (although hidden, all of these animals did survive for a long time). I have seen Brittle stars in a Mediterranean aquarium but the ones found in the intertidal here tend to live under rocks and I never saw one back in the aquarium. A Sand star Astropecten irregularis quickly buried itself in the gravel:
Filter feeders: I quickly realized that filter feeders, mussels or tunicates for example, were very difficult. There simply were not enough algae growing in the water to feed them (unfortunately, at times there were plenty of algae growing on the rocks and on the glass). One way to keep filter feeders is to separately cultivate algae for food. A really nice blog describing such a project can be found here. Another solution might be to feed these animals with artificial plankton, which is available commercially. This requires very good skimming to get rid of excess nutrients though. Both options I find too cumbersome at the moment. Having said all this, one filter feeder managed to survive for many months in my aquarium: the variegated scallop.
Other fussy eaters: Worm pipefish did OK in the aquarium, but that was probably because I regularly brought in new seaweeds housing fresh zooplankton. Unlike Mullet, Gobies or Blennies, I have never seen them take frozen food and therefore I will not keep them again until I can provide them regularly with live brineshrimp or similar. Snakelocks anemones always did well in the aquarium, but Beadlet and Strawberry anemones didn’t (they actually did not die but seem to shrink rather than grow over time). The former are able to grow because of their symbiosis with photosynthesizing algae and so do not rely as much on food. I must say that the latter two species are probably relatively easy to keep when you make the effort to regularly dunk a piece of dead prawn on them. The European cowrie Trivia monacha feeds on tunicates which I had trouble keeping alive and so they are unfortunately not an option yet:
Unknown reasons: On a few occasions a species just died and I had no idea why. The only thing this taught me was to not try that species again. This happened to a Common starfish Asterias rubens:
Welcome to this most obscure of blogs, my dear reader. The aquarium is a bit of a mess at the moment for a variety of reasons. First of all there are a lot of algae growing; I have a bag with Rowaphos hanging in the back compartment to remove phosphates but this does not seem to help much (I have had good experiences with before though). Second, one of my pumps broke and so filtration runs at half capacity. Third, the mixed success of planting many different seaweeds has left loads of detritus in the tank. I have made large water changes which helped a bit. An additional tank for experimenting would be nice to have… Fourth, I have been unlucky with some of the seaweeds: the Wireweed grew really well, but the large size meant it caught a lot of the current and was easily dislodged. The Dudresnay’s whorled weed Dudresnaya verticullosa was growing really well (see here) but broke off from the rocks and could not be replanted:
I could not attach the fine red seaweed (see last post) either and did not want to have it floating around so I have removed it. My nice red seaweed streaming from the pump outlet, most probably Devil’s tongue weed Grateloupia turutu (as the name indicates, another invader from the Pacific), broke of. A crap picture of both weeds:
I changed the white gravel with finer, beige Maerl gravel (Cornwall’s equivalent of coral sand, see previous post) here placed in a bowl for contrast:
I released my Shanny as well as the largest of the two Rock gobies. The former attacked to many of the snails (it was getting a bit of a mollusc graveyard) and the latter was just too voracious in general. The final straw was seeing it swimming around with half a Worm pipefish sticking out of its mouth (I still have a bunch of those). The Shore rockling did not survive, but I caught a glimpse of the Shore clingfish when I removed some of the rocks from the aquarium. The juvenile albino Edible crab (if that’s what it is) and the European sting winkle Ocenebra erinaceus I recently caught both still do well, as is a juvenile Shore crab Carcinus maenas:
The Netted dog whelk Hinia reticulata is not one of the most impressive looking snails, but they do very well in the aquarium, burrowing and moving around:
I am not sure whether replacing one of the actinic lamps with the daylight lamp was such a great idea, the tank looks too yellowish now, especially with the Maerl sand…However, I will stick with it and see whether it helps future attempts to successfully keep Bushy rainbow wrack Cystoseira tamariscifolia (i.e. to retain it’s iridescence). If not, I’ll go back to the original lighting. I will not do too much with the aquarium in the near future as I want to get rid of the algae first. There are not many critters in the tank, which should help (I have only introduced a nice big Snakelocks anemone Anemonia viridis recently). I will do some more water changes and order a new pump. Only then will I slowly start experimenting with seaweeds again.
I am still unsure about the chiller, but with the weather getting warmer it might be more than just a luxury to have one. Apart from the price, it standing on the floor next to the aquarium with tubes sticking out is what I don’t like about the idea though. It will also not be silent, but perhaps I could get away with disabling the noisy hood fans, resulting in an overall quieter aquarium. The stripped-down tank (note that the red encrusting algae/seaweeds at the top of the tank have died (turned white) as they were exposed for a couple of hours when changing water):
When looking for pictures of the squat lobster, I realized I have quite some neat old pictures to post. I should have started the blog when starting up the aquarium to keep things chronological, I will use the next couple of posts to get rid of this back log. First the fish. I have two Rock gobies Gobius paganellus in my tank. The big one is voracious and after a feeding session has a visibly distended belly. It is a curious fish that often comes to check me out when I am taking a picture. It is beautiful too:
However, I will attempt to catch it and release it, as I suspect it to be a bit too large (three inches) and rash. My worm pipefish Nerophis lumbriciformis are very shy and they might be bullied by large gobies and blennies. I actually suspect the big rock goby to have eaten my recently disappeared beautiful little Montagu’s blenny Coryphoblennius galerita, a species I have only found one time:
A worm pipefish Nerophis lumbriciformis. To replace the rock goby, I will try to catch some Two-spotted gobies Gobiusculus flavescens later. This species is also beautiful, but smaller and it spends more time in the water column which is nice. It is not a rock pool inhabitant though; it lives among seagrass. I have seen many last year when snorkelling. I need to look into a good net to catch them! I had two large Shannies Lipophrys pholis as well that I released again, I still have a small one left:
I also had three thick-lipped mullet Chelon labrosus in the tank. These fish are quite ugly as adults, but juveniles are nice, restless silver fish. All fish mentioned above are benthic (hang around the rocks rather than in the water column), whereas this species mostly swims at the surface and so really adds to the aquarium. I released these three when changing up the tank once and I now regret that. They are fast swimmers so quite difficult to catch (at least with the small aquarium net I use). Since they are so restless I did not manage to take a decent photograph. I have also added a Shore rockling Gaidropsarus mediterraneus and the cling fish the Cornish sucker Lepadogaster purpurea at one point. I should have known that these were mistakes as these are fish that mainly hide under rocks and I have not seen them since adding them to the aquarium. I will post some pictures of these fish in their natural habitat later.