Venturi with standard submersible?
- Thread starter JoelNB
- Start date
BeanAnimal
Premium Member
Joel a venturi is just a device that creates a pressure drop when fluid passes through it. We use the pressure drop to draw air into the water stream. Your pressure washer uses it to draw soap in...
In most cases the bubbles will not be suitable for skimming, they will be far too big. A needle wheel pump is a pump where the regular impeller has been replaced with an impeller designed to chop water instead of pumping it efficiently. The idea is to chop the air bubbles to a size suitable for skimming.
In most cases the bubbles will not be suitable for skimming, they will be far too big. A needle wheel pump is a pump where the regular impeller has been replaced with an impeller designed to chop water instead of pumping it efficiently. The idea is to chop the air bubbles to a size suitable for skimming.
I hear that the needle-wheel pump is inefficient at pumping water if it's designed to chop air.
Are you saying that people use a normal pump, followed by a venturi and then a needle-wheel pump to chop the air? (or a needle wheel pump with it's own air inlet for that matter, and no external venturi)......or can I do away with the normal pump?
If so, do I need to get a needle-wheel pump that has a pipe fitting for an inlet, so I can fit a venturi before it (the venturi just drawing water from the sump?). So will the needle-wheel pump draw enough water on its own to do the job after modding it for chopping?
Are you saying that people use a normal pump, followed by a venturi and then a needle-wheel pump to chop the air? (or a needle wheel pump with it's own air inlet for that matter, and no external venturi)......or can I do away with the normal pump?If so, do I need to get a needle-wheel pump that has a pipe fitting for an inlet, so I can fit a venturi before it (the venturi just drawing water from the sump?). So will the needle-wheel pump draw enough water on its own to do the job after modding it for chopping?
rustybucket145
New member
With skimmers the volume of water isn't really what you're going to be concerned about. You want fine bubbles, and tons of them. The most 'efficient' skimmers are re-circulating, (ie, bubbles get chopped and re-chopped) with a very low water turnover rate.
BeanAnimal
Premium Member
Joel, there are many different kinds of skimmers.
In the simplest form, a pump feeds water into the skimmer body and air is introduced via an airstone and air pump.
A needle-wheel or mesh-wheel pump can be used to feed a skimmer or recirculate water through the skimmer body. You first need to get a better understanding of how skimmers work before you set out to build one.
A venturi can be used on the output side of a pump, where the pressure from the pump drives water into its throat. The throat restriction causes the water to speed up and drop in pressure. The pressure drop allows air to be pulled into the through via a vent. You would need something AFTER the venturi to chop up the air. This not normaly done, as it is inefficient.
A venturi can also be used in an aspirating role, where it is placed on the input side of the pump. In this role the suction head from the pump pulls water through the thoat and also helps to create suction on the air intake. The air is then chopped by the pump before being pushed into the skimmer body.
In the simplest form, a pump feeds water into the skimmer body and air is introduced via an airstone and air pump.
A needle-wheel or mesh-wheel pump can be used to feed a skimmer or recirculate water through the skimmer body. You first need to get a better understanding of how skimmers work before you set out to build one.
A venturi can be used on the output side of a pump, where the pressure from the pump drives water into its throat. The throat restriction causes the water to speed up and drop in pressure. The pressure drop allows air to be pulled into the through via a vent. You would need something AFTER the venturi to chop up the air. This not normaly done, as it is inefficient.
A venturi can also be used in an aspirating role, where it is placed on the input side of the pump. In this role the suction head from the pump pulls water through the thoat and also helps to create suction on the air intake. The air is then chopped by the pump before being pushed into the skimmer body.
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I can see that it sounds like I really don't know what I'm talking about but I have been reading about skimmers for several weeks now. I have a sound understanding of the workings of a venturi and the principle of protiens attaching to the bubbles.
Where I am lacking is in the application. I have decided that I want to use a pump to drive the skimmer, rather than one of the airstone types. I have a regular pump and want to know whether I need to get a needle-wheel type to do it this way. I don't necessarily want to be original, more to build a skimmer that is tried and true.
Where I am lacking is in the application. I have decided that I want to use a pump to drive the skimmer, rather than one of the airstone types. I have a regular pump and want to know whether I need to get a needle-wheel type to do it this way. I don't necessarily want to be original, more to build a skimmer that is tried and true.
BeanAnimal
Premium Member
That is not a needlewheel, that is pretty much a standard impeller for a small pump. It will do a little bubble chopping. The venturi would go in the intake side of the pump, where the water gets sucked on. Just drilling a hole in the cover is not going to do the trick.
Are you looking for skimmer plans? What size tank? What is your budget? What kind of livestock? What is your setup like. Knowing those things will help us guide you towards a suitable design.
Are you looking for skimmer plans? What size tank? What is your budget? What kind of livestock? What is your setup like. Knowing those things will help us guide you towards a suitable design.
Well, yes I'd appreciate recommending some plans, thanks.
I'm planning a 125G in wall and I want to collect and prepare all that I need before I start. I'd be happier to build than spend where possible. I plan to use aragocrete filtering and keep community fish and low to medium light corals. I will have MHs, a protien skimmer and maybe a denitrator.
I'm planning a 125G in wall and I want to collect and prepare all that I need before I start. I'd be happier to build than spend where possible. I plan to use aragocrete filtering and keep community fish and low to medium light corals. I will have MHs, a protien skimmer and maybe a denitrator.
