Logic Masters Deutschland e.V.

AnalyticalNinja and I decided to each set a pencil puzzle combining two genres that were randomly determined with a spinner; we ended up getting Spiral Galaxy + Aquarium. You can check out his resulting puzzle here.

Rules:

Tentaisho: Divide the grid into regions of orthogonally connected cells. Each region contains exactly one circle and is rotationally symmetric around the circle.

Aquarium: Shade some cells in the grid where shaded cells are treated as water and tentaisho regions are treated as aquariums. Each aquarium is filled with water up to a certain level, or left empty. The water level in each aquarium is the same across its entire width.

Arrows: A cell with arrows has a value equal to the size of its region. That value also equals the amount of shaded cells in the arrows' directions combined, not counting the cell itself.

Solve online:

Penpa+ (answer check triggered with edges and gray shading for water)

SudokuPad (no answer check)