Need a little bit of help I have been running my air assist off

Need a little bit of help I have been running my air assist off of an old air brush pump. I have noticed lately that it is not putting out as much air as it once did and I think it will fail on me any day now as I have worked the thing to death over the past year preforming an action it was not designed to Donny running it long hours day after to day. For once I want to be proactive in replacing it. I was looking at an aquarium air pump but was unsure as to how big I need to get for air flow

The ones I am looking at range from about 500gph to about 1700gph. Any idea what the best size is to get

I’ve been using an airbrush pump like you. I have a flow gauge in my system and I’ve been running 10-20 lpm (160-320 gph) depending on the job. I am also using the LO air assist head. So I think the 500 gph would be sufficient.
As a side note, I have been using a fan (actually the stock blower) to blow on my airbrush pump to help keep it from getting too hot and hopefully prolong it’s life.

@Nedman yea I haven’t been doing that and I noticed I had flakes of metal in my water trap the other day so I think my piston is about shot as it runs very hot all the time but a fan on the pump is a good idea

i use an aquarium pump that is rated for 60lpm (no idea if its accurate as i don’t have a flow meter to check) but it seems to be more than adequate for the job. After a good few hours of running it might be warm to the touch, but that’s about it.