Dialing in Flow on AquaUV 25 watt

[ilyad]

Hi all,

I just plumbed my 25 watt Aqua UV into my return on my 75 gallon (80 gallon total water volume) tank. I ended up opting for the 25 watt since the smaller one said it can only handle up to 75 gallons (which I was above).

However, now I am concerned that the required flow rate (based on the manufacturer) is 800-1200 gph! That is 10-15x turn over per hour and seems like a ton of flow! I am using a Vecta M2 and currently running at 65% which is yielding a modest 235gph (measured using the GHL flow meter). I definitely have room to increase the flow, but not sure if it can get to the 1000gph rate.

So my question is this... can those who actually have a similar sized tank and UV let me know what they are running through their UV? Also, if you have other sized tanks but can explain the flow rate/turn over to me better, so I can calculate the flow for my application, that would also work. I obviously want to have enough flow to cool the bulb properly, but does it need that much?

Seems like the recommended rate is much higher than what is written pretty much anywhere else. Even if I went with the smaller option, it says 466-700gph (over 8x turn over).

So is my UV way too overpowered for the flow I can get out of my return?

Id like to know the recommended rates for both algae and pest control, although I will stick to one or the other. I am not sure yet which though.

 

[CoralB]

I use a 25 watt UV on a75gallon tank with a 15 gallon sump . I run my UV on a manifold which I adjusted to turn the water over thru the manifold around twice the volume of the tank roughly 150 -200 gph because slower contact time with the UV is more efficient. If you don’t have a manifold you can run a separate line to the UV then into the sump or tank . That what I do in my other larger tank .

 

[kinetic]

You'll need a dedicated flow just for the UV, rather than using it inline with a return line (which I'm assuming is what you're doing). So maybe just get a pump that's just for feeding water through the UV.

The standard is getting one pump for return, and one for "accessories." Accessories include UV, chiller, reactors (like GFO/Carbon, etc), and anything else that might need specific flow rates.

Then you can also just build a manifold (one outlet from a pump divided with T lines and flow controlled with ball or gate valves). You can measure the flow coming through each outlet.

In this case it sounds like you only need one pump dedicated to it, so it should be pretty simple to setup.

 

[ilyad]

You'll need a dedicated flow just for the UV, rather than using it inline with a return line (which I'm assuming is what you're doing). So maybe just get a pump that's just for feeding water through the UV.

The standard is getting one pump for return, and one for "accessories." Accessories include UV, chiller, reactors (like GFO/Carbon, etc), and anything else that might need specific flow rates.

Then you can also just build a manifold (one outlet from a pump divided with T lines and flow controlled with ball or gate valves). You can measure the flow coming through each outlet.

In this case it sounds like you only need one pump dedicated to it, so it should be pretty simple to setup.

I disagree that the standard is a separate pump for your UV. The recommended set up is to have all water filter through the UV, hence the best set up is your return feeding the UV. Otherwise you’re either bypassing some (water pumped by your return) or double filtering (if you’re outputting back into the sump and then recirculating back into into the UV).

I think most people just prefer to set up a UV from a separate pump because it’s much easier to do so. In any case, I don’t have the room in the sump to run an additional pump. And it’s already plumbed to run off the main return.

Mostly trying to find out what flow needs to pass through the UV as most places list much lower flow than the manufacturer themselves. and oddly, Aqua UV lists waaaay higher flow rates than any other UV manufacturer. I just can’t imagine their design being so different that it would warrant that kind of turn over and still be effective.