The ornamental design for an aquariumcleaner, as shown and described.
FIG. 1 is a perspective view of an aquarium cleaner showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a side view thereof;
FIG. 5 is the opposite side view of FIG. 4 thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The broken lines shown in the figures are included for the purpose of illustrating portions of the aquarium cleaner and form no part of the claimed design.