Aquarium Update 16

It has been more than five months since the last update on my Red Sea Max 130D so high time for nr 16. I have bought a media basket to force the water more through the filtration material, which cannot be a bad thing, but otherwise have done very little. I have not been diving as much as I wanted, and still have not gone to any of the deeper sites where I perhaps could have found some Dahlia anemones, larger Brittlestars or other interesting things. I have a red seaweed growing from the rocks; it has encrusted all rocks in a deep red colour and grows out of in a bit of a lettuce-shape. At first I thought it was the invasive species Grateloupia but the shape and colour are a bit different, I will enquire at the Seaweeds of the NE Atlantic facebook group what it is. I have some green algae but they grow in tufts that can be easily removed so I cannot complain really. Below a shot of the tank, it does not look great but there you have it:img_7419The anemones are still so-so. I think that plumose anemones need very fines foods and water changes, which I do not really do and as a result they are often closed and not growing. The strawberries and beadlets still don’t do as well as they did, no idea why. My Red-speckled anemones (Anthopleura ballii) on the other hand do great and are my favourites. Below a photo of a specimen I collected at a good low tide in Flushing this week and one in my aquarium that has grown quite a bit. It fluoresces in the middle. img_5611img_7401I have some squat lobsters rummaging around as well as a cool hairy crab. I have got rid of prawns as they are so aggressive! Every time I opened the hood and stopped the pump, they came swimming to the top, legs tickling and scraping on the plastic and attacking my fingers. They are part of the reason that my fish have not fared too well. I had some Pollack for a while but they eventually succumbed. I believe my flow is on the strong side, and with an occasional missed feeding and less energy, the prawns and anemones will not tolerate any slip up! I caught some Sand smelt (see here for two videos) with my big net from the quay but these formed a meal for other inhabitants within the day. I caught a Topknot (by hand) (see here) but that disappeared after a while too. I have two or three Cornish suckers that do well though. As soon as I feed they stick their noses from under rocks and dart out to catch some defrosted shrimp but otherwise you hardly see them. I was lucky to catch a bright green juvenile Ballan wrasse Labrus bergylta of the quay which does great (they are not as nervous as the more common corkwing wrasse). I caught another individual (I only ever caught three) but the first one started picking on it, changing from bright green to a more subdued marbled green. I was not in time to release one of them and the second fish died unfortunately.


Aquarium Update 7

Long time no post, just been too busy! The aquarium is doing reasonably well at the moment, especially considering the fact that I have not done any water changes since the last update and I have added a bunch of new organisms. I have added two Beadlet anemones Actinia equina. They are a dullish brown (except for a nice blue band around the base); I have not found the bright red or green individuals yet. Very similar but more striking are Strawberry anemones Actinia fragacea of which I have collected three. They are voracious, I could easily feed them a shrimp a day. The same goes for the Sea scorpion. I am afraid of sticking my hand in now as it comes after me! Time to let this buddy go. This will also give me the opportunity to add some other things such as squat lobsters.IMG_4825I have taken a break from experimenting with seaweeds and am focusing on anemones instead. I have added a bunch of small Plumose anemones Metridium senile that I scraped of the side of a pontoon. Weird fellas, they can fill up with water to be quite large, or just reduce to a crumpled little pancake. I have four white ones; I could only find very small ones of the orange variety and these were all devoured by Cushion stars (interesting). I’d like to have a large orange one as well, but I have to wait half a year until I can go diving again (they are very common in deeper water).

IMG_4812On the sheltered, silty shore of Flushing I found two small anemones attached to rock and half buried in the maerl sand. My excellent Seasearch Sea Anemones and Corals guide told me they were a Daisy anemone Cereus pedunculatus (uniform greay with many very short tentacles) and a Red speckled anemone Anthopleura balli (purplish and speckled, for a better picture of a different colour variant see this old post). Both quickly half buried/half nestled themselves under a rock so only the tentacles and the mouth are visible. They take pieces of shrimp and so hopefully they’ll be able to grow; these species should reach a decent size: IMG_4721

IMG_4729My friend marine biologist Chris gave me a snakelocks anemone that he had cured from its symbiotic algae. A very cool, bright white individual but it has returned to its original purplish colour so it must have taken up symbionts again. The snakelocks I already had, grew big, split into two and grew some more. Interestingly, one of the individuals seems to be turning from the green- to the purple colour variety:IMG_4828So six anemone species in all. I would really like to have some Dahlia anemones, they are very colourful, large, and not uncommon (old pic here). I need to go anemone hunting at a good low tide soon (I have not been out in ages).

I had the Chryseminia seaweed growing attached to the Tunze for a while and it worked OK, but it looks a bit messy and so I will remove it. However, I see that little Chryseminia plants have started to grow from the rock in many places (see top picture). I have to give the glass a weekly clean (with a tooth brush) and the rocks have turned a bit too greenish recently. I have noticed however that near the Snakelocks anemones, tufts of filamentous algae have appeared, as the grazers do not want to come too close to their tentacles (this reminds me of a work by an ecologist friend of mine who studies how seedlings can be protected from grazers when growing close to thorny shrubs, I’ll have to tell him of this observation!).

There has been some snail mortality. I mainly have Grey top shells but there are less than half of them left. I do not know why, part might be predation (which is not all bad as at least they serve as food for other inhabitants). I need to collects some more in any case. The Netted dog whelks are doing well. They are usually hidden below the sand, but as soon as they smell a defrosted shrimp, they come up like a Shai-Hulud. Their plowing through the sand is definitely good in preventing mats of diatoms to appear. Their little cousins the Thicklipped dog whelks are also doing fine. They tend to creep up the Daisy anemone to steal its food. I still have a Sting winkle Ocenebra erinacea which moves slowly but is very pretty. There are a variety of other species such as Blacklined- and Rough periwinkles. The best species however are the truly sublittoral large Turban top shells Gibbula magus (some of which have died as well, one of the shells has been taken over by a hermit crab, wich are also doing fine):


Cornish Coral

A couple of weeks back I went for a boat trip and snorkel over Maerl beds with friends on the other side of the Fal Estuary, just north of St. Mawes.  I did not post about it at the time, as my photographs were quite crap and I reckoned I could go back to try and come home with something better. However, there hasn’t been any time for that, nor will there be in the near future, and as it was such a cool experience I reckoned it would be nice to write a little post about it for now anyway. The beach was fringed with sea grass, but the Maerl beds started very near the coast, at around two meters depth at low tide. Maerl is something special; it must have taken early biologists a while to figure out whether it was mineral, animal or plant. It is actually a calcareous alga that (very slowly) grows in fist-sized nodules or thalli. The Fal and Helford estuaries are one of the few places in the country where it occurs, and the Maerl beds here are under threat of dredging. Although Falmouth has the third deepest natural harbour in the world, big cruise ships cannot land close to the town centre which makes it unattractive for ships to stop. Falmouth would be a very pretty last port of call sailing west and cruise ships are of course good for business, hence the dredging plans. I will save the debate on economy versus conservation for a future post, as it will require a lot more text. I was able to take some pictures of the Maerl with my old Canon Powershot in plastic housing before the new batteries decided to quit on me prematurely:IMG_3280As you can see the Maerl really looks more like a coral than a seaweed (and dead pieces of Maerl form a type of coral sand, see here and here). It provides an ideal structured habitat for all kinds of organisms to live in and on (for instance fine seaweeds and snakelocks anemones). Besides various fish, crabs and sponges and small things darting to safety in general, we saw a big hermit crab in a Buccinum undatum shell with the large anemone Calliactis parasitica on top. Very cool, and apparently not very commonly encountered (this was of course after my batteries had run out). What was striking as well, were the very large (one of them measured half a meter across), very fat and very pale Spiny starfish Marthasterias glacialis:IMG_3279Maerl with a sponge growing through it (or possibly the other way around):IMG_3276Maerl is protected, so not an option for the aquarium, although I am sure it would make for a fantastic looking display (moreover potentially a very stable display as Maerl is not seasonal but grows for centuries). Hopefully more and better pictures later this year!


With the aquarium ready and a neap tide, I resorted to some fishing from the quay with my humongous (>2.5 meter) net. This thing is a pain when moving/emigrating but I’m glad I’ve kept it. It is custom-made for RAVON: Reptielen Amfibien en Vissen Onderzoek Nederland (Reptiles Amphibians and Fish Research The Netherlands), a great club that I joined for a while when living in Holland. (The ‘fish’ in the acronym covers only the species living or migrating in fresh water). The net can be bought via the RAVON web shop; at the time they also sold a handy cuvet:

IMG_0483I have scraped along the sides of the main quay in Flushing a number of times now (btw, the quay was built by the Dutch; Flushing is named after Vlissingen in Zeeland, the old Cornish name of the village is Nankersey). Two-spot gobies (the most common semi-benthic species), a rock goby and even a Fifteen-spined stickleback Spinachia spinachia have ended up in the net. The last species I did not keep, as they prefer live food that I cannot offer them, but I took it home for a quick pic:

IMG_8687I never caught young mullet, a species that is great for the aquarium, which is strange as they are common around water fronts. This weekend to my surprise I caught two wrasse for the aquarium: a Rock cook Centrolabus exoletus and a Corkwing wrasse Symphodus melops. Two very beautiful little fish (both species grow up to 15 cm, these were around 5 cm). Here the Rock cook Corkwing wrasse that looked superficially like a Rock cook but back home in the aquarium showed its distinctive spot on the base of the tailfin (best way to identify is counting scales and rays but that is almost impossible now; useful info on wrasse determination on this angling site):



new year’s resolutions

It has been a while since I last posted about the aquarium, mainly because I had a problem with algae and did not like the look of the tank in general. Combined with being away for two weeks over the holiday season, I decided to remove the rocks and most animals from the tank. Only left are some snails, Cushion stars and a Spiny starfish (who seems to do fine except for being less brightly coloured than when I caught it). The snails made a good start and cleaned up a lot of algae but it was too little too late. Also, (non Spiny starfish-related) mortality was quite high. Of all snails, the periwinkles fared least well (as I had noticed on earlier occasions); the Grey top shells seemed to do best. A main problem is that the snails move out of the water and often die there. Grey top shells can be found in the intertidal but are also common in the subtidal and so might be more suitable for the aquarium.








Anyway, time for a fresh start in the new year. I have decided to buy a chiller (and pump), mainly so I can switch off the noisy hood fans, but also because a more natural temperature regime might help keeping some of the more difficult species (see eg here and here). I have trawled the internet to find recommendations for the least noisy chiller but to no avail. I will stick with a more expensive brand and hope for the best. I will also invest in LED lighting. LED lights give a nice shimmer effect, generate less heat, use less electricity, need less replacement and are more easily dimmable. I’ve found this interesting Red Sea Max 130D retrofit kit:solderless_rsm130_dimmable__09721.1361404356.640.640I will need to buy a separate dimmer and probably will have to ask my local sparky for help fitting it in the hood but it seems like a good investment. I’d like to supplement white LEDs appropiate for shallow water with some blue ones so I’ll be able to get a deeper water feel as well. This week I saw an inspirational aquarium back in Blijdorp Zoo in Rotterdam: a deep water reef with gorgonians, many brittle stars, Boar fish (or Zulu fish) Capros aper, Snipe fish Macrorhamphosus scolopax and John Dory Zeus faber. A crap photo:


However, I will go for a more brightly lit seaweed aquarium first. I will switch to finer gravel and reduce the amount of rocks to improve water flow. This time I will also focus more on fish. Marius has a great picture of a Two-spotted goby Gobiusculus flavescens in his Irish rock pool aquarium here and I definitely want to have a couple of these (I had a tiny one recently but it was eaten by one of the Snakelocks…). The other fish I definitely want to have is a bright green juvenile Ballan wrasse Labrus bergylta (although the other species are pretty too):

wrasseSmall wrasse can be caught using a hand net but I reckoned it would be easier using a cast net. After my first trial run with such a net in the Helford river a while back I am not so sure though: loads of leaves and twigs but no fish. Youtube has hundreds and hundreds of ‘how to throw a cast net’ videos but these all use slightly different techniques which sometimes involve a throw whilst holding the led line between the teeth… Anyway, I’ll have to practice!


animals that did not do that well in my aquarium…

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:


Piran aquarium

I have a love/hate relationship with public aquariums: love because I am a bit aquarium-mad, and hate because quite a lot of them really are disappointing. Of course, I know all too well that it is not easy to create (and maintain) good-looking aquariums. Also, the paying public needs to be pleased and it wants to see ‘nemo’s’ and sharks which often results in the same sets of standard tanks. Although I do understand the need to educate the public, I am quite allergic to all kinds of video installations and boring props taking up space that could have been filled with tanks. I am not even talking about walkways decorated with fake polyurethane caverns or ornamental treasure chests in tanks…

I try to visit public aquariums whenever possible and from now on will review them on this blog, specifically highlighting the smaller, temperate saltwater tanks that could serve as inspiration. Last week I was in Slovenia for work and a short holiday and passed by the lovely town of Piran which has a small (about 10 large and 10 small tanks) public aquarium, all with local animals. Here is one funky looking tank housing some writhing moray eels and Grey triggerfish Balistus capriscus, the latter also present in Cornish seas:



I am not so sure about larger-sized Mediterranean Sea aquariums, as there is not a lot of potential to make them visually appealing: some rocks and the odd human implement as decoration and the fish are often not overly spectacular (see the Two-banded bream Diplodus vulgaris below). If I were to go for a large, non-planted rock tank, I would try my hand at an African Great Lake aquarium instead, with the fish being more diverse, more interesting and more beautifully colored.


 One of the largest fish on display was the Leerfish Lichia Amia. It was a shame to see such a large pelagic fish in a tank with its head completely deformed due to it bumping against the glass:


I was most interested in the smaller aquariums. These housed some species that can also be found in Cornwall, such as the Tompot blenny Parablennius gattorugine and the fantastic John Dory Zeus faber (which occurs around the globe):



Some of the small aquariums were quite sweet. No seaweeds to speak of (although I saw some Ball algae Codium bursa) but lots of nice invertebrates such as sea cucumbers, clams, whelks, sponges, anemones as well as a variety of fish:




Especially amazing was the stony coral Astroides calycularis:


A Small rockfish Scorpaena notata:


All in all an interesting little visit (I had to rush a bit taking pics as the rest of the family is not as keen on ‘the mysteries of the deep’ as I am…). Lots of types of invertebrates that I would like to try to keep such as sea cucumbers, but for the moment I will focus on seaweeds. I had no time to have a proper look at the rocks outside (the Mediterranean has very small tide differences anyway) and I had not even brought my snorkel. From the glances I got, the Adriatic coast did not have much on the Cornish coast though!

Sea mats

A close-up of the Sea mat Membranipora membranacea taken with my olloclip macrolens for the iPhone. This Bryozoan forms colonies on flat seaweeds. Each rectangular chamber (cuticle) houses an individual zooid. Each zoid feeds on plankton using a lophophore, a group of ciliated tentacles. Zoids differentiate into specialized types, for feeding, cleaning the colony surface or as brood chambers for embryos.


A close-up of the Hairy sea mat Electra pilosa, a species very common under rocks:


new sand

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):



disturbing data

Allright, I finally have a thermometer. I ordered it online and it turned out to be way to small (not helped by the addition of the arcane Fahrenheit scale…). Anyhow, my water turns out to be 25 degrees (Celsius)! This is a couple of degrees warmer than I thought, and not exactly characteristic of British Seas. I will have to save money for a chiller…


I also bought a hydrometer (cheaper than a refractometer) to measure salinity. This was even more of a shocker, the salinity was literally of the scale! >40 g/l instead of the 35 g/l or so of ‘regular’ seawater!


I have recently started to change water more frequently, which means I have not been topping up evaporated water with distilled water but instead replacing this water of 0 g/l salinity with seawater of 35 g/l salinity. Stupid. Tomorrow I will take back distilled water from the lab for a good water change (gradual of course). My temperature and salinity values demonstrate that rock pool critters are quite hardy: all my fish and anemones seem to be doing just fine. However, who knows these high salinity levels might have caused problems in the aquarium for some of the seaweeds collected from the lower shore…


Actually, recently one organism died a week after I put it in the aquarium, probably because of the temperature and salinity shock, the beautiful Dahlia anemone Urticina felina (not a very good photo):