Schego Prima Diaphragm Set

Description

Schego Prima Diaphragm Set — Two replacement diaphragms for the Schego Prima 100 L/h air pump

The smallest pump in a range tends to be the one left running longest, in a nano tank, a quarantine tub or a breeding box. Schego Prima Diaphragm Set (SKU: SH731) is the replacement diaphragm set for the Schego Prima, the entry-level membrane air pump from Schemel & Goetz in Germany. Schego’s instructions for the Prima list the diaphragms as item 731, supplied as two pieces, which matches this set’s code. A diaphragm is the flexing membrane that does the pumping, and when it fatigues the Prima delivers less air than its rated 100 L/h.

Schego’s instructions say to replace the diaphragm if performance drops, and to replace the white pump head as well if it is heavily soiled; the head is a separate part sold as the air chamber and diaphragm kit (SH732). The Prima is rated 220–240 V at 50 Hz for indoor use only. Retailer specifications give it 110 L/h at no head and 100 L/h at 0.5 m, 3 W, a case of about 116 × 66 × 51 mm and no flow adjustment. The maker’s procedure is to unplug the pump, loosen the base screws and remove the housing cover, unscrew the diaphragm nut, loosen the screws on the metal rocker armature and lift it off, then pull off the old diaphragm. Reassembly is in reverse order, leaving a gap of about 1 mm between the magnet and the coil.

Usage & Application

When to Use

• Dropping output: The Prima’s bubbling has weakened but the pump still runs.
• Small tanks and tubs: Nano aquariums, quarantine tubs and breeding set-ups where the Prima is the working pump.
• Preventive service: A pair of diaphragms gives one change and a spare.
• Before the pump head: Try the membrane first; Schego advises replacing the head only if it is heavily soiled.

Installation & Replacement Guide

• Unplug: Pull the mains plug before undoing anything.
• Open the pump: Loosen the base screws, remove the housing cover and unscrew the diaphragm nut.
• Lift off the arm: Loosen the screws on the metal rocker armature, lift it off and pull off the old diaphragm.
• Refit in reverse: Fit the new diaphragm, rebuild the pump and set the magnet-to-coil gap at about 1 mm.

Product Specifications & Highlights

Key Features

• Two diaphragms: Item 731 in Schego’s Prima parts list is a two-piece set.
• Prima-specific: Made for the 100 L/h pump, not the larger Schego models.
• Maker-documented fitting: Schego publishes the strip-down steps in the Prima instructions.
• Restores airflow: The fix when the pump is healthy but the membrane is tired.
• Low-power pump: The Prima is listed at 3 W.

Product Details

• Brand: Schego (Schemel & Goetz, Germany)
• SKU: SH731
• Barcode (GTIN/EAN): 4005256007311
• Product Type: Spare Parts > Air Pump Diaphragm
• Schego Item: 731 (2 pieces)
• Fits: Schego Prima 100 L/h air pump
• Pump Output: 110 L/h at 0 m; 100 L/h at 0.5 m head
• Companion Parts: Air chamber and diaphragm kit (SH732); coil (SH733); air filter felt (SH734)
• Target Environment: Small freshwater and marine aquariums aerated by a Schego Prima pump