Linear piston pumps

[Mr Gumby]

Hi folks, I was browsing the good old internet for a suitable backup air pump. I currently have a 16l per minute diaphragm pump which just about does everything I need.

I've spotted a Charles Austen et35 which has double the capacity so that's good, linear so hopefully long lasting and not crazy expensive.

Only question is how do you know if it's too much and quietest method to bleed air off.

I'm not planning a closed loop , just run it off gang valves

[SantaMonica]

Too much and quietest method to bleed air off ?   Meaning, too much air, and, what's the quietest way to bleed?

[Mr Gumby]

On 6/2/2024 at 8:37 PM, SantaMonica said:

Too much and quietest method to bleed air off ?   Meaning, too much air, and, what's the quietest way to bleed?

Yes that's what I meant, sorry I didn't explain myself very well 

[Sacah]

I think you're looking for something like a "pneumatic exhaust muffler", the smaller ones just look like larger air stones, though I suspect the bigger ones to exhaust more air are a bit more complex inside. I just don't have the experience to help you know which to pick for the quantity of air you want to exhaust.

[Mr Gumby]

On 6/3/2024 at 9:38 AM, Sacah said:

I think you're looking for something like a "pneumatic exhaust muffler", the smaller ones just look like larger air stones, though I suspect the bigger ones to exhaust more air are a bit more complex inside. I just don't have the experience to help you know which to pick for the quantity of air you want to exhaust.

that's actually very helpful as I've now realised I can just run extra sponge filters and pull them out when I have fry or new fish in QT.

I would imagine 9 or 10 sponge filters and a couple of brine shrimp hatchers should use up that air 🙂

 

[gardenman]

Anytime you're looking for linear piston air pumps, check out the septic tank supplies online dealers. Those air pumps are a relatively standard item for modern septic systems and those dealers tend to buy in larger quantities and sell more than any fish store could ever hope to sell. That means they can buy in larger volumes, often at a lower price and they're facing more competition in the marketplace in terms of pricing.  While a linear piston air pump is long-lasting, they do eventually wear out, and for septic tank owners, they become a fairly common replacement item, so lots get sold for that use. You can sometimes find one at a lower price than through an aquarium retailer.