Here's my self-built rotary unit for a saltwater aquarium, used in conjunction with an SLW 20 or similar. It consists of two housings of different depths: one for single operation and the other for distribution with up to four rotary units.

This is my custom-built rotary unit for a saltwater aquarium, used in conjunction with an SLW 20 or similar. Here's the parts list:

1 pc 15x24x5mm 6802 ABEC-9 full ceramic zirconia ZRO2 ball bearing

Black nylon, M6 (20 pcs), 30mm

Black nylon cap nut M6

Black nylon, M10 (5 pcs), 20mm

D1 Mini Micro USB

3-pin DC LED strip light extension cable connector, male to female

DSpower 15kg large torque metal gear digital low-profile servo for helicopter, airplane, 1/8, 1/10 RC car, TRX4, Slash, SCX10, Arrma

Tunze silicone buffer, 19mm (6065.620)

Small screws for attaching the cover

Acrylic tube, OUTER 25mm, INNER 21mm

PVC 25mm

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