how do you determine skimmer air power?

[StrategicReef]

Trying to understand this... Liter per watt, or something what's the unit and how do you measure it?

For example if I have a Eheim 1250 pump adding a venturi, would this rating change based on which skimmer body it is being used on?

[luke33]

It would not change on what body it is used on. In this case the venturi and pump pull in the air, weather it be a nw, dd, venturi skimmer. There are lots of different venturis that can pull air but each pump is different in how it peaks its performance. It also depends on how large a volute the pump has if its a nw skimmer. A venturi skimmer and dd skimmer use the water to force in the air. You can measure the air pull with a dwyer air meter in lpm, lph or scfh's.

[StrategicReef]

but with same amount of air drawn in, a needle wheel will give me finer bubbles and more surface area then to attract waste, right?

[luke33]

Sure, if you have a venturi or dd, beckett skimmer the bubbles won't be as fine as say a NW, pinwheel or meshmod. The smaller the bubbles are the more surface area is created meaning more area for doc's to bond and be turned into skimmate. Although some argue larger bubble's attract different kinds of proteins and what not. The pump is pretty much the heart of the skimmer. It will determine how large of body and neck you need.

[StrategicReef]

Thanks.. what is dd and beckett?

[luke33]

Downdraft, or beckett skimmers. You use a pressure pump to pump air into your skimmer basically. Like an ETSS, MRC, PM, predator, ...etc.

[StrategicReef]

What about contact time, how important is that?

[gabe3d]

The skimmer body does somewhat effect the pump's ability to pump. The higher the water level in the body compared to the outside where the pump's intake is at, the harder it will be to pump water into the body. It's not really the body itself but rather where and how the water exits the skimmer. If it is recirculating or if the water level are identical then this doesn't exist.

[luke33]

Sure back pressure does affect pump's ability to pull air. Contact time is very important imo, thats why recirc's work so well.

[StrategicReef]

thanks for the advice.. Lets say if I have brand X using Eheim 1250 pump if I switch to brand Y skimmer also using with same pump is it a waste of time? Not going to be too cost effective right to mess with right?

Although one has a mesh wheel and one does not but it boils down to actual skimmer design for the win.