Skip to content

Replacement Diaphragm Kit for Supreme Hydroponics AP-20




The Danner Diaphragm Kit provides all the replacement parts you need to extend the life and performance of Danner AP-20 models, including the Supreme Hydroponics AP-20 Air Pump. Each kit comes with a variety of replacement parts including a diaphragm, flapper valves, plastic slip washers, and a bottom pressure chamber gasket.

Out of stock

Your Garden's Success is our #1 Priority

HTG Supply is committed to providing you with the very best products, pricing and service in the industry. We will ship your order fast and discreetly packaged to protect your privacy. Buy with confidence knowing your HTG Supply purchase includes simple returns as well as lifetime product support. Call our team of real growing experts with your purchasing or product use questions, and we will be here to help!

See it for less somewhere else? Give us a call and we’ll beat any online competitor’s price!

Customer Service:  1-866-710-GROW (4769) | [email protected] | Hours: Mon-Fri 9:00 a.m. to 5:00 p.m.


Diaphragm Kit for Supreme Hydroponics AP-20

Replacement Diaphragm Kit for Pondmaster AP-20 Air Pump Item# 04520, Supreme Aquarium Oxy-Flo AP-20 High Volume Air Pump Item# 04220 and Supreme Hydro Oxy-Flo AP-20 High Volume Air Pump Item# 40522.

Kit Contains:

  • Diaphragm
  • Flapper valves
  • Plastic slip washers
  • Bottom pressure chamber gasket

Installation Instructions:

  1. Disconnect the pump from the AC receptacle and from any hoses.
  2. Remove the cover lid by removing screws on the bottom
  3. Unscrew the diaphragm/flapper combination assembly from either end of the pump and separate the two parts.
  4. Open the flapper valve housing, remove the flapper valves and replace them with the new ones. Be sure to maintain the same front and back side orientation of the flapper valves.
  5. Remove the round diaphragm completely and replace it with the new diaphragm and slip washers supplied.
  6. Replace the diaphragm/flapper assembly and refasten.
  7. Replace the cover lid.

Diaphragm Air Pump Repair Kit Manual

Weight .01 lbs
Dimensions 3 × 3 × 3 in


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.