Flow for UV in sump

[Axelrodi202]

I have a 400 gallon freshwater (I know... but you reef folk are so smart about tech) discus aquarium (335 gallons in tank and rest in sump). Right now I have an Aqua UV 57 watt unit running on the first compartment of the sump. I know some may say this is not ideal but I want the water to go through the UV before the biological filter (due to UV helping break down some organic waste compounds). Measured flow is about 420 GPH.

My main goal for the UV is to reduce bacterial load in the water. The water is clear (though perhaps the photo will end up being blurry) but of course discus prefer a lower bacterial load. Looking at Aqua UV's website the recommended flow rate is from 1200 to over 3000 GPH for this 57 watt unit. I happen to have an 1800 GPH pump lying around. Would there be any benefit to using this rather than the current pump? I'm not sure how much of an effect the increased flow would have if the UV is circulating repeatedly on the same first chamber of the sump. But at least more water would be turned over without overly reducing pass time through the unit?

 

[Ooh fiddlesticks]

Is say stick with what you have now, 420 gph on a 330 gallon tank is somewhere in the neighborhood of 125% turnover per hour, which is enough to sterilize the water, keep it clear and keep the bacteria load down.
I don’t know how many hours per day you’re going to be running it but I’d think one or 2 hours per day would be sufficient.
With a higher flow pump you’ll get less contact time and in turn the unit won’t be as efficient.
Of course, what does the manufacturer recommend?

 

[Ooh fiddlesticks]

Nice discus tank btw.

 

[Axelrodi202]

Is say stick with what you have now, 420 gph on a 330 gallon tank is somewhere in the neighborhood of 125% turnover per hour, which is enough to sterilize the water, keep it clear and keep the bacteria load down.
I don’t know how many hours per day you’re going to be running it but I’d think one or 2 hours per day would be sufficient.
With a higher flow pump you’ll get less contact time and in turn the unit won’t be as efficient.
Of course, what does the manufacturer recommend?

The manufacturer says the following:

at 30,000 µw/cm2 (EOL) GPH: 3,200 (Max Flow Rate)
at 45,000 µw/cm2 (EOL) GPH: 2,133
at 60,000 µw/cm2 (EOL) GPH: 1,600
at 75,000 µw/cm2 (EOL) GPH: 1,280
at 90,000 µw/cm2 (EOL) GPH: 1,066 (Min Flow Rate)

 

[Ooh fiddlesticks]

The manufacturer says the following:

at 30,000 µw/cm2 (EOL) GPH: 3,200 (Max Flow Rate)
at 45,000 µw/cm2 (EOL) GPH: 2,133
at 60,000 µw/cm2 (EOL) GPH: 1,600
at 75,000 µw/cm2 (EOL) GPH: 1,280
at 90,000 µw/cm2 (EOL) GPH: 1,066 (Min Flow Rate)

I’m not familiar enough with uv jargon to make sense of that, but hey, at least I can admit my shortcomings!
But if there’s a minimum flow rate (1066) it might not hurt to swap pumps

 

[Ooh fiddlesticks]

Hopefully someone with more experience chimes in.