Freshwater

Difficulty: easy

Difficulty: easy

Difficulty: advanced

Difficulty: advanced

Difficulty: easy

Difficulty: easy

Difficulty: easy

For tanks of 20–100 l

For tanks of 10–50 l

For tanks of 150–250 l

For tanks of 20–100 l

For tanks of 200–350 l

For tanks of ≥ 200 l

For tanks of 150–400 l

For tanks of ≤ 100 l

For tanks of ≥ 200 l

For tanks of 100–250 l

For tanks of ≤ 100 l

For tanks of 150–250 l