Besides the underwater sight into the basin of the seals a 2500 l containing North Sea aquarium presents smaller living creatures within the living space of the seals. If you search long enough in the sand and look at carefully you will suddenly notice an eye. This belongs to the flounder (Platichthys flesus) waiting for prey - hidden and having matched its colour to the ground. Each female is laying up to 2.000.000 eggs of which symmetrically grown larvae slip after 5-10 days.
A sea scorpion (Acanthocottus scorpius) is wrathfully looking out of its cave. Sea scorpions are greedy animals feeding on everything passing their big mouth. They are not poisonous although you may think so because of their name. Only the stings on their gills and on their fin streamers can enter deeply in your skin if touching and can cause painful irritations. The spawn is laid in clumps on the ground and is watched by the male for about 5 weeks until the youngs are slipping. A special spawn biology can be observed relating to the eel mother (Zoarces viviparus). Upon the internal fertilization 30-400 eel shaped youngs are developing from yolk-poor eggs inside the female.
Sea-spiders and hermit crab belonging to the group of crabs are living in the basin. The sea-spiders (Hyas araneus) can move only slowly. Therefore they often stitch with their claws barnacles and alga tuffs on their back-shell to approach to the starfishes being their main food in a well-screened manner. The name is misleading: sea-spiders do not belong to the eight-legged spider species but to the 10-feet crabs. The hermit crab (Pagurus bernhardus) has another problem: his hindquarters is not “shielded” and has to be protected by means of a snail-shell. If his apartment becomes too small he has to move to a bigger shell and during this move he easily becomes a prey. Hermit crabs feed on every- thing being good to retrieve and what they can shovel with the smaller claw into the mouth. They look like plants but being animals. Purple roses (Actinia equina) belong to the anthozoas or corals. They exist in many colour variants. Above the stout body there are standing a lot of tentacles around the mouth opening. Fishes, molluscs and crabs are paralysed with the nettle poison and then crammed into the mouth by using the tentacles. They could become up to 70 years.