Species details: Crangon crangon

I always manage to catch at least a few brown shrimp whenever I go shrimping, irrespective of location, time, tide, or time of year. They do alright in the aquarium, although they do not seem to like temperatures much above the 20 degrees Celsius. They prefer a sandy substrate and spend most of their time buried, with only their eyes protruding, but are easily tempted into showing themselves with frozen or flake food, and also come out at night.
They do not do well in the presence of larger fish, and also have a habit of bumbling head-first into waiting anemones. I guess they do not encounter many anemones in their natural habitat, and they do not seem to be able to avoid them as easily as a prawn can, for example. Although they are a bit drab, they are actually quite entertaining to watch and exhibit a range of interesting behaviours. They are interesting inhabitants and do well, provided they are kept separate from their natural predators.

Species details: Carcinus maenas

Shore crabs are easy to catch and ubiquitous, and they adapt extremely well to aquarium life, being tolerant of high temperatures, fluctuating salinity, and poor water conditions.   I still found that adding them to your tank is a very, very bad idea, as they are highly aggressive and make short work of their tankmates, including fish. Even small crabs grow rapidly, and they can be very difficult to remove, especially if the tank contains a lot of rock. They also spend most of their time hidden away out of sight, so the only sign of their presence is the dwindling number of other livestock. Luckily they are easily lured into traps. I would not recommend this species, unless kept on a tank of its own.

Equipment: Skimmer

Although not hugely powerful, the skimmer makes a big difference to water quality, especially when there is a mass sporulation of algae, which can turn the water a bit turbid. It's a good little skimmer that's unobtrusive within the tank, and produces about 50ml/day of concentrated skimmate if running smoothly. The only complaint I have is that the inlet hole is a bit small and regularly clogs with algae, which basically stops skimming. On the other end, the outlet also becomes clogged with algae, in which case it over-skims. I guess most marine skimmers are not designed to cope with large amounts of vegetation as most will be run in reef systems. If I were to set up a new system, I would probably choose a model with larger inlets and outlets, or attach some form of strainer to keep out algae.

Equipment: Lighting

The tank is set up to simulate the environment of the lower shore of the English Channel, so good growth of macroalgae is an important issue. I have tried different combinations of different tubes, and found that this one gives me the best growth while also giving attractive lighting. I used to have two Power-GLOs, but I found the light to be too red, and the colours of the animals and plants weren't as luminous as they are now. Plant growth is very good with the current combination.

Equipment: Cooler

There are very few species that can be kept successfully for any stretch of time without a cooler. I can't think of any fish, only prawns and beadlet anemones, as well as common shore crabs.
I have got a 300W model, but in retrospect I would probably go for a more powerful model. My cooler is a bit noisy, I don't know if this is a feature of the model in particular, or just my particular one. It was advertised as being quieter than a domestic refrigerator, but sound more like a washing machine. It does the job though, and takes about an hour to cool the water by one degree.
The back and sides of the tank itself are insulated with aluminised foam, and the tubing to and from the chiller and external filter are covered with plumber's pipe insulation.

Equipment: Pumps

I consider good flow to be vital for the maintenance of the tank. I initially had weaker pumps, but only when I switched to Koralia Hydor 4 did blue-green algae stop being a problem. I also get the best flow of macroalgae in the regions of highest flow, probably because the area is kept clear of more loosely attached nuisance algae. My two pumps are at opposite ends of the tank and run constantly, but presumably the results would be even better if they were pulsed to increase turbulent flow. I might even upgrade at least one of them to an even more powerful pump.
Maintenance is a constant chore with these pumps as the inlet slats quickly become clogged with fragments of red algae. I have high levels of primary production in my tank, and the removal of algae is one of the main mechanisms of phosphate and nitrogenous waste removal. I only do a partial (1/4) water change every six months (!), and the phosphate and nitrate levels nevertheless remain below the detection limit of the commercial tests. I used to change the water much more regularly, but I found that this only upset the stability of the system. My tank is not comparable to a tropical reef system because of the lush growth of algae, and frequent removal of algal biomass is very efficient in removing pollutants.

Species details: Spinachia spinachia

I originally had three, all from Falmouth (Cornwall), but only one grasped the concept of frozen food. As the other two only accepted live food even after a month, they got to go back to sea. I like this species for its uniquely rigid posture, a bit like a horizontal seahorse, but feeding is really a problem. Even the one that accepts frozen food needs many feeds a day, presumably because the body is too thin to hold a lot of food in the stomach. Apart from that, this peaceful species seems hardy as long as temperatures are kept down.

Species details: Lipophrys pholis

My shanny was caught by hand in a rockpool at Lulworth Cove (Dorset) in November 2009 and was previously in another setup. In spite of its large mouth, it is relatively peaceful even towards much smaller fish such as my two-spot gobies. It has however recently learned that the prawns are vulnerable when they have just moulted, and has eaten a few of the smaller ones. It accepts most foods and will even take dry flakes or pellets. It is hardy and tolerant of higher tempartures for short spells.
The great thing about all blennies I have kept is that they really have unique identifiable characters. Some are shy and hide most of the time, others are highly inquisitive, and some are just plain aggressive, but they all seem to be aware of the world outside the tank and will often react to the presence of people.

Species details: Labrus bergylta

I was very lucky to catch a juvenile of this species along with my corkwing wrasse. When I caught it it was around 3cm in length and the brightest emerald green I have ever seen in a fish, easily rivalling tropical marines in terms of sheer colour. It adapted well to life in the tank and accepted frozen food straight away. The colour has become a bit less intense now that it is older, but it is still impressive. I expect the colour to remain green until it is around 15cm, but I will probably let it go again before it reaches that size, as it would be a bit big for my tank.
It mostly ignores my other fish, but seems to be territorial against the corkwings. It does tolerate them most of the time, but occasionally will briefly chase them, although it never fully attacks, and the corkwings are generally only mildly impressed.

Species details: Crenilabrus melops

I caught mine at Southbourne (Dorset) by blindly swiping a rocky pier with a large net in waist-deep water. They were about 2cm when I caught them in August. They are very interesting little fish that exhibit a variety of behaviours and interact well with one another, with no sign of aggression. They do however worry the plaice sometimes by nipping at their fins. I don't think that this it out of aggression, but rather because they mistake the fins for an item of prey. Apart from that they seem to be peaceful, and easily accept most foods. 

Species details: Gobiusculus flavescens

I caught mine in a marina in Falmouth (Cornwall). They are surprisingly easy to catch, as you can easily approach them slowly with a net until you are within striking range and then scoop up a few at a time. The shoal reforms after a short while at nearly the same place, and you can get more. I only took four because my tank was well-stocked already.
They really are the perfect mid-water fish for a temperate marine setup. They are attractively patterned, small, stay together in a loose shoal and readily accept frozen foods. The pupils of their eyes are highly reflective, which gives them a slightly spooky appearance. Contrary to other gobies I've kept, they always remain in mid-water and only settle down on the substrate at night. They do not harass each other or any of the other tank inhabitants.

Species details: Pleuronectes platessa

These were caught using a shrimping net at Southbourne (Dorset). I've been shrimping at many other paces as well, and generally I catch the most flatfish on an incoming tide in knee- to waist-deep water from April to June. During these months, I nearly always catch young flatfish while shrimping, mostly plaice, plus some sole/solenette.
Once in the tank, it usually takes them about a week to figure out that frozen food is edible, but after that they feed voraciously on almost anything. I usually feed mysis and brineshrimp. They are relatively active, and although they spend most of their time on the bottom, they rarely dig themselves into the sand, and also spend a surprising amount of time swimming freely in mid-water. They are not agressive to other livestock or each other, and often even lie close to or even on top of one another. They are a bit more sensitive to elevated temperatures, which should not exceed the low twenties, but are robust and easy to keep otherwise.

Species details: Patella vulgata

I have one large specimen from the groynes at Barton-on-Sea (Hampshire) that is stuck to the rear glass of the tank. The only trace of activity is that about a square foot of the glass is kept free of algae. It doesn't usually stray far from its home, but once it surprised me by turning up on the side glass of the tank. Before that, I had assumed that it wouldn't be able to navigate a right angle between two panes because its shell would get in the way, and I still don't know how it did it.
It isn't much to look at, but it's useful for keeping the glass clean, and I might get a second one.

Species details: Palaemon sp.

I love prawns. I'm not exactly sure which species I have, and they never hold still long enough to get a good look at their rostra. I have some from Falmouth (Cornwall) and some from Lulworth Cove (Dorset), and I suspect that they are different species, the Cornish ones being P. elegans and the others P. serratus. Their behaviour is identical, all being very active and constantly investigating objects with their legs and antennae, which makes them very useful in keeping the tank clean. They get a little to inquisitive sometimes and will nip at my arms during tank maintenance, but do not harass any fish. The females will sometimes carry eggs, but I've never had any larvae; I assume they get sucked into the filter.

The are very attractively coloured, hardy and resistant of even very high temperatures, easily tolerating up to the high twenties for a few days.

Species details: Porcellana platycheles

These are from Lulworth Cove in Dorset. I have three, but I never see them, they are always hidden between the rocks, and don't even come out after dark. Occasionally I get a glimpse of them when I shine a torch between the rocks, which they don't seem to mind. They seem quite hardy, but they are so secretive that its like they aren't there at all. I guess they make themselves useful by feeding on detritus between the rocks.

Species details: Actinia equina

These are a mixture of red and green colour morphs from the groynes at Barton-on-Sea (Hampshire). They are relatively easy to gently pry off the rocks, but if the occasional individual decides to stay put, it's better to let them be rather than harming them. I started out with about six, but they rapidly started reproducing. The young anemones tend to hide deep in the crevices between the rocks, so I am not sure how many there are now. They come out into the open when they have reached about 1.5-2cm disk diameter. Then they are not shy of light, and seem to prefer regions with medium flow. They do not move around much once they have found a suitable spot.
They often retract their tentacles, but unfurl them as soon as food is added to the water, and are very pretty then. They don't seem to bother any of my current livestock, but I have had small fish taken in the past. I do not feed them specifically, and they seem to get by fine on scraps.
I have found this species to be very hardy. I had them before in a smaller tank without any cooling, and they thrived even with temperatures staying in the mid-twenties for weeks. I really recommend this species.

Species List

Invertebrates

Cnidaria
     Beadlet anemone (Actinia equina)
     Snakelocks anemone (Anemonia viridis)
     Plumose anemone (Metridium senile)

Mollusca
     Sea hare (Aplysia punctata)
     Common cockle (Cerastoderma edule)
     Slipper limpet (Crepidula fornicata)
     Green saccoglossan (Elysia viridis)
     Grey top shell (Gibbula cineraria)
     Green ormer (Haliotis tuberculata)
     Laver spire shell (Hydrobia ulvae)
     Common periwinkle (Littorina littorea)
     Dog whelk (Nucella lapillus)
     Common mussel (Mytilus edulis)
     Common limpet (Patella vulgata)

Anellida
     Ragworm (Nereis diversicolor)

Tunicata
     Light bulb sea squirt (Clavelina lepadiformis)
     Ciona intestinalis
     Dendrodoa grossularia

Crustacea
     Broad-clawed porcelain crab (Porcellana platycheles)
     Prawns (Palaemon sp.)
     Common shore crab (Carcinus maenas)
     Hermit crab (Clibanarius erythropus)
     Brown shrimp (Crangon crangon)
     Hermit crab (Diogenes pugilator)
     Leach's spider crab (Inachus phalangium)
     Mysis shrimp (Neomysis integer)
     Marbled rock crab (Pachygrapsus marmoratus)
     Risso's crab (Xantho pilipes)

Echinodermata
     Cushion star (Asterina gibbosa)
     Purple sea urchin (Paracentrotus lividus)


Fish

     Corkwing wrasse (Crenilabrus melops)
     Two-spot goby (Gobiusculus flavescens)
     Ballan wrasse (Labrus bergylta)
     Shore clingfish (Lepadogaster lepadogaster)
     Shanny (Lipophrys pholis)
     Plaice (Pleuronectes platessa)
     Sea stickleback (Spinachia spinachia)
     Pollack (Pollachius pollachius)
     Common goby (Pomatoschistus microps)
     Solenette (Buglossidium luteum)
     Sea bass (Dicentrachus labrax)
     Lesser sand eel (Ammodytes tobianus)

About the setup

Tank       Fluval Roma 200 with external canister filter

Lighting   one 36'' T8 30W Hagen Power-GLO
               one 36'' T8 30W Hagen Life-GLO

Skimmer TMC V2 Skim 200 Compact

Pumps    two Hydor Koralia 4

Cooler    D&D DC-300


Salinity 3.5% (Reef Crystals)
Temperature max. 20 degC

Substrate 1:1 mixture Dorset pea gravel/coral sand, 2-3 cm layer
30 kg Cotswold stone

Running since 05/2010