Making a canopy - fan cfm?

[Myka]

I found some Nidec Beta V brushless fans at Princess Auto for like $3 each. They are 12VDC (I bought an adapter to wire on), 0.29 amp, and apparently 43 cfm and 36 dB. 36 dB sounds like a lot, but I wired one up to the adapter and it's a heck of a lot quieter than the fans that are in my Degenbao fixture!!! Anyway, if I have two 43 cfm fans, one sucking into the open top canopy, one blowing out is that significant or should I look for some bigger fans? It doesn't feel like it's moving much air.

[banditpowdercoat]

Average conversation is 71dB

Sound level Doubles every 3 dB so 36dB is ALOT quieter than 71 :D

Ya gotta love PA. Im heading there Wed in PG.

The fans may be enough? it all depends on your canopy, and lights. How sealed is it? where you place the fan's? I would try different ways. If wanting to remove the heat in the canopy, jusrt putting them in the top, pulling UP wuould work great. But then that does nothing for the heat that the lights put into the water. For that, fans blowing across the water, between lights and surface of the water are best. My canopy will have inlet fans on ends, and exhaust fans on top.

Also, the more little fans you use, the more independently you can controll them. Get just the right amount of cooling needed at all times of the year. Gets a little warmer, turn a couple more fans on.

[Myka]

Hehe, yes PA is awesome for some stuff. I also found some gas shock thingies like used to open a hatchback car for $10 each. I was going to use them to open the top and hold the lights up, but I think they are going to be too strong. They are 265 lbs, and only 13" long. Will take quite the lever to close them and I don't think an 18" canopy will be enough.

This whole DIY thing sucks...I really don't enjoy it at all. Grr...

I didn't think of using any fans going upwards...that's a good idea. I need to figure out a way to have the lights out of my way so I can get in the tank easily. This is why I was thinking of using the shocks to lift the lights out of the way.

[banditpowdercoat]

LOL, kinda funny, it's the DIY aspect that I love most about reefing. I allways like creating someting

[Myka]

You're nuts. :p

[banditpowdercoat]

LOL, Your avatar is sooo fitting for that last statement too :D

I can just picture it, sitting at your computer, scratching your head, wondering WHY in H@## would someone like that?? LMAO

[Myka]

Hahahaha!!! I chose the avatar for purpose ya know! Believe it or not I found it on a Google search...

[AndyL]

86cfm is plenty - but don't have one pulling & one pushing... Use a passive air intake (down at the bottom of the fixture) both fans at the high point pulling hot air out; try to ensure you're not restricting the intake (lots of info on how to size an air intake can be found on google).

As for the gas charged shocks - Bet you'd find they're useable, but you might have to play with the moment arm a bit - becomes a trade off between opening enough vs opening/closing easily... Betcha bandit could make you a pretty drawing to show what I'm trying to say...

[oilfieldsafety]

I got my fans from Memory Express, if my memory serves they are running 37cfm at 18 db. I love how quiet they are, I have 2 pushing and 2 pulling from left to right, they work great and you cannot hear them.

Shane

[banditpowdercoat]

Just so everyone's on the same page here, 2 fans in a push pull config will only push the fan rating. ie, 2 50cfm fans in a push pull, will only move 50cfm. Now, put them both the same way, Pulling air, or pushing, with adequate inlet/exhaust. They will now combine to equal 100cfm

[Myka]

Good point on the pulling/pushing. Never thought of that. The canopy is going to be open top and open back, so there shouldn't be any flow restriction.

I understand the lever action of the gas shock will make 265 lbs not as bad as it sounds, but I still think it will be a lot for a 40ish lb canopy top...?

I'm thinking I'm going to rip my Degenbao fixture apart and use the "guts" to retrofit everything onto a piece of plywood, then the plywood will lift up and down with the shocks (or something). I might just skip the shocks, it won't be that heavy. I could put the fans right in the top of the plywood pushing air out. Then the actual canopy "wrap" will be removable from the front, just side it off like the AGA ones. That's the best idea I can come up with keeping ease of assembly in mind.

[mseepman]

This sounds like my kind of idea...keep us posted as you do the "tear apart and rebuild"

[Myka]

I'm scared Mark!!! :lol:

[banditpowdercoat]

Meh, nothing to be scared of.