February 26, 2017
I didn't get around to updating this blog any more even though the plankton project has been running at a steady pace all the time since my last update about a year ago. At that time I was planning on setting up a new macro algae aquarium. But I decided against that. Then I started to think about an aquarium without any flow at all and experimented with that a bit. Then I wanted to set up a non photosynthetic tidal flow aquarium, but decided that I didn't have the time to build a new tank and work with it now, so I decied to just set up a small tidal flow experiment in the aquariums I currently have running. That experiment has been running for a few months now. I haven't taken many photos or written down much over the last year, but since many people have asked for updates I thought I should just take all the photos I have and put them out in a sort of summary of the year.
Small tidal currents are treasure chests for collectors. In this current I found scallops, large horse mussels, squat lobsters, porcelain crabs, a large dahlia anemone, whelks, worm colonies. The brown color is from the 25cm deep layer of humic brackish water on top. Below it was clear sea water.
Here are many different animals. Porcelain crabs (Pisidia longicornis), squat lobsters ( Galatheas squamifera), some unidentified shrimps, the largest brittle star is probably Ophiothrix fragilis.
Whelk (Buccinum undatum).
Just some photos I like.
One of my neighbours.
His food, perhaps.
Seen on a weekend car trip in the mountains. Presumably boreal owl (Aegolius funereus).
A fresh coldwater aquarist on his first tidepooling trip.
I was thinking about setting up an aquarium with almost no flow at all. Just the flow generated from some air bubbling and about 0.33 times per day water circulation through filter and refugium. I have noticed that many animals really don't like much flow. This is true for some shrimps and fish. I sometimes see large dahlia anemones (Urticina eques) in very sheltered spots. Clams and sea squirts generate their own local feeding flow. The idea of a quiet and peaceful environment where small fish and shrimp could go around on their daily business seemed appealing. I was asking myself what kind of animals that would thrive in a flowless aquarium with lots of phytoplankton. I had read that squat lobsters ate algae, but I had never seen them touching any macro algae. It seems like they actually eat phytoplanton. Their mouth parts are shaped like fine brushes that they use to scoop up plankton that has landed on the bottom. So then my flowless aquarium should be the perfect place for them. Porcelain crabs are also squat lobsters. But they take plankton straight from the water with highly specialized mouth parts. It should be great for them too. So I decied to get some from my favourite tidal currents. And it was not hard to find them. I have also been lucky to find a spot where I can collect the beautiful pink shrimp (Pandalus montagui).
Here is a sand shrimp (Crangon crangon) and pink shrimp (Pandalus montagui), just after I caught them. I don't remember the number, it is a bit hard to tell how many there are in the jar. But this was in october last year, and several are still in fine condition.
I decided to change the aquarium into a tidal current biotope. Mostly because 3 of the 4 species of colorful aquascape forming animals available to me need much flow. There is a video of it below.
This was a fantastic trip to a sheltered bay deep in the fjord Lurefjorden. I know of a tidal current with just the right speed. This is the only place anywhere where I have been able to find sea cucumbers (Cucumaria frondosa). It was also a wonderful spot for just snorkeling. I collected one adult that I have kept for 6 months now. It has stayed in one spot all the time. Now that there is good flow it has its tentacle crown out all the time.
Here is another one of my many attemps at making insulated glazing. Because of the difficulty with mounting it on an installed aquarium with 4.5C temperature in the water I am not sure if it worked this time either. We will see. Getting closer at least!
The plan now is just to keep the tidal flow setup going the rest of the year. I want to improve the aquascape a bit with some more animals. I have a rock with soft corals on (Alcyonium digitatum), but there are only a few small colonies and it is in the back. It would be great to get a smaller rock with a larger colony. I want some more clams too, and a few visible dahlia anemones (there are some that are hidden). Judging by the cloudiness of the water there should be plenty more food.