Is VCA Random Flow Generator worth it?

BurgerFish

Well-Known Member
View Badges
Joined
Jul 26, 2018
Messages
503
Reaction score
215
Rating - 0%
0   0   0
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
 

DarkSky

Well-Known Member
View Badges
Joined
Jan 23, 2017
Messages
863
Reaction score
1,053
Location
Minneapolis, MN
Rating - 0%
0   0   0
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

Active Member
View Badges
Joined
Aug 20, 2019
Messages
424
Reaction score
533
Location
San Jose, California
Rating - 0%
0   0   0
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
 

NickC

Active Member
View Badges
Joined
Oct 29, 2018
Messages
240
Reaction score
281
Location
California
Rating - 0%
0   0   0
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

Active Member
View Badges
Joined
Aug 20, 2019
Messages
424
Reaction score
533
Location
San Jose, California
Rating - 0%
0   0   0
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

Active Member
View Badges
Joined
Oct 29, 2018
Messages
240
Reaction score
281
Location
California
Rating - 0%
0   0   0
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.
 

PerplexyHexy

Valuable Member
View Badges
Joined
Sep 8, 2016
Messages
1,560
Reaction score
1,970
Rating - 0%
0   0   0
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...
 

Vivid Creative Aquatics

Upgrade Your Flow!
View Badges
Joined
Oct 12, 2017
Messages
1,517
Reaction score
2,166
Location
Phoenix, AZ
Rating - 0%
0   0   0
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. :)
 
OP
OP
BurgerFish

BurgerFish

Well-Known Member
View Badges
Joined
Jul 26, 2018
Messages
503
Reaction score
215
Rating - 0%
0   0   0
One 3/4 return will work fine with two VCA RFG 3/4 with 1000gph?
 

AJsReef

Valuable Member
View Badges
Joined
Oct 19, 2017
Messages
1,121
Reaction score
1,061
Location
North Florida
Rating - 0%
0   0   0
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
 

Vivid Creative Aquatics

Upgrade Your Flow!
View Badges
Joined
Oct 12, 2017
Messages
1,517
Reaction score
2,166
Location
Phoenix, AZ
Rating - 0%
0   0   0
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

Active Member
View Badges
Joined
Dec 2, 2013
Messages
281
Reaction score
218
Location
ohio
Rating - 0%
0   0   0
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

10K Club member
View Badges
Joined
Oct 28, 2014
Messages
14,091
Reaction score
20,005
Location
Stamford, CT
Rating - 0%
0   0   0
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

Well-Known Member
View Badges
Joined
Feb 11, 2016
Messages
813
Reaction score
635
Location
Maine
Rating - 0%
0   0   0
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.
 
Back
Top