Freshwater

For tanks of ≤ 200 l

Difficulty: easy

For tanks of 100–150 l

Power 3 W

Difficulty: easy

For tanks of 150–250 l

For tanks of ≤ 500 l

Difficulty: easy

For tanks of 10–40 l

Difficulty: easy

For tanks of 20–500 l

Difficulty: medium

For tanks of 200–1500 l

Difficulty: medium

For tanks of 100–750 l

Difficulty: easy