Idea for Pumilio vert air circulation

bellerophon · #1 (**permalink**) 05-11-2007, 04:49 PM

The beginner pum thread got me thinking about how I could convert a regular vertical tanks vent to a recirculating vent. Here's my thought so far. what do you think?

defaced · #2 (**permalink**) 05-11-2007, 04:56 PM

Looks pretty good. Let me make sure I'm looking that this drawing right, you'd have two fans, one drawing air into this insert and one pulling air out, is that correct? This way it'd just be moving the air inside the tank, not bringing new air into the tank?

bellerophon · #3 (**permalink**) 05-11-2007, 05:36 PM

almost, except it would be one fan at the center rather than two at the ends. would be easy to fab. and easily removable. and this would only protrude from the tank 1.25"

pl259 · #4 (**permalink**) 05-11-2007, 05:52 PM

Why not just mount the fan on one end instead of in the middle, perpendicular to the front? this way it could stick out less than 1.25. Taking it even further it could be recessed into the tank without it sticking out at all.

Some thoughts,
EricG.NH

bellerophon · #5 (**permalink**) 05-11-2007, 06:04 PM

I tried that first but the airflow was far too turbulent unless I increased the radius of the outer curve. It certainly could be recessed though, I was simply looking for a "stick on" version to adapt one of my vertical tanks that already has a vent in place. There's obviously easier ways of doing this as other already have, I just like the idea of it being mobile and easily fitted without modifying the tank at all.

Tripod · #6 (**permalink**) 05-11-2007, 09:18 PM

Nice idea so far. I like anything that is modular or works as direct replacement of an existing part.

As far as actual air circulation, I think this design would tend to move the air only at the uppermost portion of the viv. Circulation from top to bottom would be prefered. That might be difficult with this design.

How about adding a ninety degree elbow, of sorts, to one of the holes and have it pointing down? This would at least push (or pull) some air from the levels below the vent.

Corpus Callosum · #7 (**permalink**) 05-11-2007, 11:44 PM

If the fan is built to recirculate the air, make sure it can take the humidity of the air it will be moving constantly.

pigface · #8 (**permalink**) 05-12-2007, 01:24 AM

That's similar to the ones I just built for my new tanks . Mine are kinda crude compared to your drawings though . Mine are on the top rear of the tanks above the background , you can't see them so I didn't take the time to make them look pretty . Yours look like they will go on the front in place of the glass vent ? If so mine haven't helped keep the glass clear any , so far .
The fan is inside a totally sealed enclosure so it just moves the in tank air and the fan is sealed over a screened opening on the left side , it sucks inside air through another opening on the other side of the enclosure . They don't blow real hard but you can feel air movement through the other hole .

( The front fan is for glass ventilation , and are not hooked up yet . )

I've had them on going a week or so , Right now the circulation fans come on with the lights and run constantly and the tank I have a humidity gauge in says 90% so far , and this might go up once the substrate gets saturated and the broms fill up . So keeping them running all the time hasn't lowered the humidity so far like I thought it would .
I'ts only been a week so it's too early to tell if there will be any benifits .

sbreland · #9 (**permalink**) 05-12-2007, 06:01 AM

I really like the idea and think that it has possible real applications. The problem I see is the size of the fan... the one Brent uses for his is a 6 inch fan and mine use 3 inch fans to do the work. I would be concerned that the small fan wouldn't do much except create a draft rather than actually circulating the air. I have a new design that I am working on but it is meant to be built in at the time of construction so would not fit the application like you have there. I have no idea how to draw the pics on the computer like the one you did aboe or I would show exactly what I was talking about.

Mark, if yours isn't keeping the glass clear, it's probably not moving enough air. I run mine on cycles because leaving it on constantly actually tends to dry things out too much, but when the fan comes on the glass clears in a couple of minutes. I need to perfect this new design and figure out how to draw those pics....

pigface · #10 (**permalink**) 05-12-2007, 10:15 PM

Stace , I used a small fan because I also have the other fan in the front also moving air . They move a decent amount of air for a small fan . A 6" fan , wow . I wan't to move a little air not uproot all the plants ! The 120 mm fans I have for my lights move ALOT of air , I can't imagine a 6"er . Maybe in a large tank though . My tanks are only about 20 Gal .