Is VCA Random Flow Generator worth it?

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BurgerFish

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Hi,

I want to try a VCA Random Flow Generator.

I have a 3/4in tubing and around 1000 GPH return.

I want to install two 3/4in VCA Random Flow Generator.

It's a good idea? Many members here try to sell those generators, perhaps they don't like them?

Thanks
 
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DarkSky

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They don't work unless you have A LOT of flow moving through them. I had the 3/4" versions installed on two 3500 gph pumps in my 220g, I'd have to run the pumps at 80%+ for them to create random jets of flow - at that flow rate the noise and flow through my sump was too much for me.

I think it'd be better if you went with a smaller version and used your 1000 gph pump. Less flow needed to work correctly.
 

splitting_lanes

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At 1000gph, I’d suggest the 1/2” RFG. Two at the most.

i have an octovarious 2 with a 1/2” rfg and I run it at 60% now.

the RFGs work great, but they take some experimentation to dial in for your tank. I assume some people just give up and that’s why they sell them
 
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I had a 3/4” one on my return and it worked great. Only reason I pulled it off, is that I had to keep it too far under the surface so that it wouldn’t suck air through the back of it. Keeping it that far underwater meant my return would back siphon too much water into my sump when the power went off.

Other than that it worked as advertised, matter of fact I really liked the random/far spread of flow it provided.
 

splitting_lanes

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I had a 3/4” one on my return and it worked great. Only reason I pulled it off, is that I had to keep it too far under the surface so that it wouldn’t suck air through the back of it. Keeping it that far underwater meant my return would back siphon too much water into my sump when the power went off.

Other than that it worked as advertised, matter of fact I really liked the random/far spread of flow it provided.
I had the same problem, and I drilled a 1/8” hole in the return above the RFG, and it stopped the excessive backflow. Bonus was it also prevents the RFG from sucking air off the surface when it’s really cranked up.
 

NickC

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Yea, I did that too. I can’t remember the exact circumstances but for some reason I was still having issues and took it off. Just been running open 3/4” locline ever since.

I have 3 mp40’s in my 75g, so flow was never big enough of an issue to mess around with it again I guess.
 

Waynerock

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Hi,

I want to try a VCA Random Flow Generator.

I have a 3/4in tubing and around 1000 GPH return.

I want to install two 3/4in VCA Random Flow Generator.

It's a good idea? Many members here try to sell those generators, perhaps they don't like them?

Thanks
One word...YUP!
 

PerplexyHexy

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Yeah... I have them on all my tanks... proper GPH is extremely important when running them though... with proper flow through them they work quit efficiently... just as well as some powerheads IMO...
 
AS

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Hi,

I want to try a VCA Random Flow Generator.

I have a 3/4in tubing and around 1000 GPH return.

I want to install two 3/4in VCA Random Flow Generator.

It's a good idea? Many members here try to sell those generators, perhaps they don't like them?

Thanks

The main things you want to do to get the most out of a set of Random Flow Generator™ Nozzles is to choose the right size based on the flow you can provide them. All of our RFG Nozzles have a Minimum GPH and "Suggested optimal GPH" ratings. if you can supply the RFG the suggested optimal GPH (or more), you'll get a very pronounced randomized flow out of it.

to help you visualize the the different sized RFGs at various flow rates, we have a YouTube playlist that goes through a few different GPH scenarios. We purposely inject micro bubbles to the return line so you can see the flow - might be helpful to check it out:

Also, as some have pointed out they do need to be fully submerged to both work property and to prevent them from drawing in air. Here's a quick start guide that can help you get the best randomized flow AND position them as close as possible the surface.

RFG-Installation-Guidlines-1.jpg


Hope that helps. Should anyone here reading this, have any questions, please do not hesitate to call us, email us and post your questions here. :)
 

AJsReef

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Depends on tank size and other flow. I removed mine in favor of cone returns when I moved up to 4x MP40 as I didn’t see the need and prefer more surface agitation than they offered. I also found that they had to be positioned just right or else they sucked air occasionally for a rather unpleasant noise
 
First Choice

Vivid Creative Aquatics

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One 3/4 return will work fine with two VCA RFG 3/4 with 1000gph?
Yes - I think it would work well. But you'll want to make sure your actuality delivering 800 -1000 GPH to the outlet, after any head pressure generated by the plumbing.

If it's 1,000 GPH at the pump, but less than 800 at the actual nozzle, then you may be better off with a single 3/4in RFG.

In terms of creating a randomized flow pattern, a single RFG will perform better at or above the suggested Optimal Flow Rating than two RFGs being supplied with less than the optimal GPH.

hopefully that makes sense. If you have any additional questions, please do not hesitate to ask.
 

mrbh22

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has anyone played around with one of these on a sea Swirl? i would like to think that would be an ideal situation to create really random flow patterns across a wide section of the tank. i would be curious to see if the back pressure they create would interfere with the mechanics of the sea swirl
 

ca1ore

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I had a 3/4” one on my return and it worked great. Only reason I pulled it off, is that I had to keep it too far under the surface so that it wouldn’t suck air through the back of it. Keeping it that far underwater meant my return would back siphon too much water into my sump when the power went off.

I am using a pair to good effect on my closed loop but not in the return for exactly this reason.
 

fermentedhiker

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has anyone played around with one of these on a sea Swirl? i would like to think that would be an ideal situation to create really random flow patterns across a wide section of the tank. i would be curious to see if the back pressure they create would interfere with the mechanics of the sea swirl
I have them on my sea swirls. They work great except that the outlet of the sea swirl places the nozzle pretty close to the surface so the nozzles will sometimes start little air vortices from the surface if the sea swirl isn't perfectly level.
 
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