Bi weekly Discussion ~ Skimmers!

[tims]

Well Welcome back to the Bi-weekly discussion!!

It has been a while since had this up and running. In case you are new or not sure what this discussion is about.. this first topic will be on skimmers. it is a open discussion so feel free to ask anything you want to know about skimmers or share your knowledge with us!


Skimmers;
lets jump right in and bang out some info about them!

What exactly is a skimmer anyway?
Why is it important to have a skimmer? or is it really THAT important to have one?


well?

[jenajet]

I really really really wouldnt want to see my 90 without a skimmer on it! With the Volitan and his eating and pooping habits my water would be black and nothing would survive. My skimmate has literally been almost black more than once. I mean where would the stuff go if we didnt find a way to export it?

[Loverotties]

I agree,we'd have to do water changes every day!

[dobejazz]

Great Topic Tim glad to see the discussion of the week back!

So what is the difference in a beckett style and venturi style or are they the same thing

[JY13131]

OK, I thought we were starting with the BASICS! What is a skimmer? What is it for? At what size tank with what inhabitants does one need a skimmer?

[Sambo]

I'm good at basics!! Here is my 'broad brushstrokes' understanding of what it is and does:

A skimmer is a device that mixes air (as bubbles) and water at high speeds. Dissolved organic substances (ie waste products) become bound to the bubbles and are removed from the water column as foam. rather like the foam you see washed up on the beach at the seaside. This foam can then be removed by emptying the collection bucket.

I am not too sure as to the merits of each (someone help me out here) but I think the method for producing bubbles varies depending on the pump used (needlewheel, beckett are 2 common types) - size of bubbles also seems to be important (is small better??)

And that's as much as I can contribute usefully....

[Diving The World]

I find that small bubbles and a lot of them are better than large bubbles. I use a wooden airstone hooked up to a Rena air pump (by far the most powerful and quiet I've used. I've tried using the water pump to add bubbles but it forces them to hard into the skimmer allowing them to escape the outake.

I also find that if I have the airstone too low in the skimmer, it will cause the bubble to escape through the outake and I get a tank filled with bubbles.

Hint - If using an airstone/air pump, make sure your pump has a air control valve. As your airstone deteriorates, you will need to turn up the air pressure. It will also allow you to dial it down if there is too much foam overflowing into the collection cup.

[Diving The World]

As for what size? I have a 29 gallon with one. I'd say as small as you can actually operate one on it. My first saltwater tank was a 2.5 gallon in about '83 (4th grade, seems like yesterday!). I don't think skimmers existed then, but obviously it wouldn't have fit.

How do you newfangled nano guys do it, skimmer or no?

[tims]

Kelli we will get to that soon!

[wharyat]

I run an AquaC Urchin on my 20.

I'll touch on the injector, venturi, and needlewheel.

An injected skimmer uses an injector () to accelerate water into a column of standing water. When the accelerated water meets the standing water there is an immense amount of turbulance that cause air to be mixed with the water.

A venturi uses the Bernoulli effect to draw air into the water stream. The Bernoulli effect is when flowing water meets a constriction in a pipe which causes it to accelerate; the water on the intake side is high pressure (due to the constriction) and the ouput side is low pressure. When a hole is drilled in the constriction, air is pulled in (due to a vaccuum between high and low pressure) and mixed with the water.

A needlewheel can rely on the same principals of a venturi, but the venturi is placed before the pump. They can also just be done with an air tube located near the pump as it will supply air just from the vaccuum force of the pump.


These are all just a way (without forced air) to add air to the water.

[wharyat]

Originally Posted by tims

Kelli we will get to that soon!

Sorry Tim.

[Dagrape]

How do you tune a skimmer to get either wet or dry skimate? I have heard lots of talk about both, but nothing on how to achieve either one.

[tims]

Originally Posted by wharyat

Sorry Tim.

thats okay! you did good.. but we will come back to that in a litte bit. i would like to break all of that down a bit more . also go in to the pros and cons.

Originally Posted by Dagrape

How do you tune a skimmer to get either wet or dry skimate? I have heard lots of talk about both, but nothing on how to achieve either one.

the skimmate is the gunk / proteins and organic sludge that the skimmer makes. often times when a skimmer is new it needs a break in time to "relief" the skimmer surfaces from its postive static charge.
but when the skimmer is set to have a lot of air going to the skimmer it will cause the amount of water and air mixed to spill over in to the collection cup. this is the "wet" skim. the dry skim is the lower air intake and you get a "foam" to slowly fill the collection cup. as this fills up it leaves a nice gunkie sludge on the riser of the collection cup and really realy smells great!.. it is often servered as patte` at parties!

[Diving The World]

Originally Posted by Dagrape

How do you tune a skimmer to get either wet or dry skimate? I have heard lots of talk about both, but nothing on how to achieve either one.

I use an air pump, so I just adjust the pump valve pressure up or down. It allow me to tune very precisely.

[Dagrape]

Gotcha.....I kinda figured but I hate assuming so I usually just ask anyway. Thanks for the info.