Air Diffusers and Air Pumps

[smithvillemike]

I have a Dolphin AV150 air pump. It says, "Will pump down up to 14.5 feet. Pumps 150L/min or (5.3 CFM) 6.57 PSI" Can I attach it to a 9" air diffuser, 5' down, but 15 feet away from the air pump without any appreciable loss of air pressure. I want to put the diffuser over my bottom drain.

thanks

Mike

[kntry]

Mike, are you DIY the BD? I'm going to order 2 diffusers tomorrow to make MCA's BDs.

I can't answer your question but I do know that the smaller the tubing and the longer the distance, the less air delivered.

[smithvillemike]

Originally Posted by kntry

Mike, are you DIY the BD? I'm going to order 2 diffusers tomorrow to make MCA's BDs.

I can't answer your question but I do know that the smaller the tubing and the longer the distance, the less air delivered.

Don't get me in trouble with this group.

No, it is a retrofit 2" that I am putting in next weekend along with the no niche skimmer.

Mike

[kntry]

Why, are DIY projects a bad thing?

[smithvillemike]

not that it is a DIY, but the fact that retro drains are only 2" and not 4".

[koiczar]

Mike

The answer to your question lies in the size of air tubing you plan to use. I would recommend 1/2" ID to at least a two way valved manifold (you can make this with pvc and 1/2" ball valves. Then reduce the size coming from the open end of the ball valves to 3/8". You can use the grey thread/barb fittings to change your ID needs from 1/2" to 3/8". then attach 3/8" ID tubing to your diffusers. Just add one diffuser besides your BD so you can regulate the air. Also, in case the BD isn't enough air flow, it won't put too much back pressure on your pump. 5' deep 15 feet away should NOT be a problem for this pump!

Mike

[smithvillemike]

Thanks Mike I appreciate you help.

Mike

[MCA]

you only need 3/4" ID tubing from the air pump nipple to the nipple that should be the termination of the 1" pipe from the BD to to the filter pit. I use an Dolphin on each of our BDs which are at 8' depth.

My experiences with the Dolphins is that they do NOT deliver as much as air as an Airtech 120. But, the deliver more than an Airtech/Alita/Hakko 80. I would estimate them to be more realistically be 100L pumps.

As a 100L air pump, they seem indeed to be a bargain.

[nguyen4]

Do you really need air diffuser at BD or not? I just start shop round for my new pond, about 6000gls water. Some friend told me air diffuser at BD will get dirty soon and hard to clean out. He recommend me used air stone will better. is that right? (i will drill hole and put air line inside BD but used big air stone for it. Any idea about it?

[koiczar]

Originally Posted by nguyen4

Do you really need air diffuser at BD or not? I just start shop round for my new pond, about 6000gls water. Some friend told me air diffuser at BD will get dirty soon and hard to clean out. He recommend me used air stone will better. is that right? (i will drill hole and put air line inside BD but used big air stone for it. Any idea about it?

Nguyen

Whoever told you that was not totally correct. Actually the air "bladder" that is used on a BD diffuser will last a whole lot longer than an air stone before clogging. You'll have to change your airstones at least once a year and clean them in a solution of muriatic acid or bleach to open the pores again. The "bladder" is usually a piece of EPDM rubber with tiny little laser drilled holes. There's nothing to plug up. Just stay with the BD diffusers. Use airstones in your filters so they are easier to get to when they need servicing.


MCA

Mike, sorry, I mis-read the size of his Dolphin pump. I thought it was the AV-50 not the 150. Actually, the AV150 comes with a rubber piece that connects to the pump and the other side fits 1" PVC exactly. We used it when we connected the BDs on our last customer's pond. They're 20-35 ft away from the pump and with the manifold, totally adjustable and working great.

Mike