Autumn cleaning

Some days ago we started with the most fun part: cleaning the mesocosm bags from outside with a window scraper and a brush operated by a diver.

It may sound strange since our experiment is inside the bags, but we don’t want to have algae growing on the outside and shading the inner environment.

It is tough work since with every stroke of the brush you get out of your balance and have to swim steadily to keep the pressure.msswat-0325447

From the inside we clean even more regularly. F   or this we do not put the diver into the mesocosms but use a ring with a rubber lip, which just has a little bit bigger diameter than the mesocosm bags, so it takes off gently what is growing on the inside walls.

Every two meters a stabilisation ring keeps the bag in shape, which the ring has to pass, for this we tilt the ring a little bit and it slips through easily.

The diver in the water saw no algae being taken off the walls, which is good, since we want to clean before wall growth even happened.

So clean and nice the mesocosms are now waiting for the deep water to be put in.