The Bicolour Blenny, scientifically named Ecsenius bicolor from the IndoPacific, is a very good fish to have in the marine aquarium. For the majority of aquarists the qualification for livestock to join the aquarium community requires specific attributes, mainly colourful beauty, or strange and unusual shape or comic appearance. There are so many beautiful fish, an obvious smaller one is the Flame Angel and a larger the Emperor Angel. There are lots and the reefs supply this in various sizes including, thankfully, small. There are also the different fish, still attractive. A different fish example is the Longnosed Hawkfish which has a habit of sitting on rocks watching the world go by, seemingly a little aloof from the hustle bustle.
The Bicolour Blenny then. The fish can grow to around 4 inches (circa 10cm) and is easy to look after being generally hardy, this makes it suitable for beginners and the more advanced. A reef aquarium suits it well as it lives in crannies or caves between the rocks. It is a generally bottom dwelling species and is a herbivore so algae for it to graze on is required, thus a more mature aquarium is an advantage. If algae is in short supply then it should be made available for the fish. Algae based flake food is available and also other algae foods. The fish will investigate and take other foods too but algae is necessary generally.
In general, as with most fish there could be arguments though these small occurrences don’t normally lead to anything more serious. However the risk increases, again as it does with many other species, if there is another fish of similar colouration and size as there could be territorial disputes. So there is a need to avoid similarity in colour. As far as corals are concerned the fish is not considered a risk though it could mouth a coral, perhaps testing to see if it is eatable.
Much like the Longnosed Hawkfish the Bicolour Blenny could sit on rocks and watch their world pass by for a while before going off to look for food. As already stated they are a bottom dwelling species and, if there is decorative sand in the aquarium, they could shift this around to an extent to meet their requirements.
There is a downside, one that could never appear but needs attention just in case. Though generally a bottom dweller they are considered to be good jumpers and it isn’t a pleasant thought that the fish could be found outside the aquarium one day. This doesn’t decrease the desirability of the fish as the potential problem is easily dealt with. Some very thin mesh could be placed over the aquarium, held tight by a very light wooden frame. The frame goes all the way round the aquarium resting on the inside top strengthening struts. If the aquarium is large then two or more frames could be made. When maintenance is required the frame(s) are very easily removed. The mesh should not interfere with light delivery as the result could be detrimental to the corals. The mesh can be of very thin string forming not too small holes. Alternatively, glass covers could be considered.
The Bicolour Blenny is a different fish. It is colourful, a prime requirement. It has habits that are different such as sitting around from time to time. They also have a facial look that seems intelligent and inquisitive. Viewed straight on they might seem to be wondering ‘Now what do you want?’