Sterilizer

[Jack Milam]

installing a UV sterilizer What’s the best way to determine how much flow you have running through it. Installing on a manifold

 

[Quietman]

2 different circumstances requiring different flows (or selecting the right size UV to handle both). To damage/eliminate algae issues (dinos for ex) you need to have at least 8x flow to get ahead of reproduction rate and have at least 30,000 uw/cm2 exposure (the vendor should have the specs). To eliminate pathogens (ich/velvet) exposure at least 90,000 uw/cm2 (and some list up to 120,000 or more). So you'll have to do a little math on the flow rate at the different exposure rate (it's linear calculation so fairly straight forward - flow is proportional to exposure) to determine size you need.

You can go with one and a variable speed pump or big enough UV and fixed flow to cover both (8x flow at higher exposure rate - that becomes impractical with very large tanks) or two separate UVs and pumps (but who's going to do that, right?).

Manifold isn't optimal but it'll work. You're only taking a portion of tank flow so exposure rates are lower. Best to put in direct return line or closed loop. If have to be manifold maximize flow.

 

[Jack Milam]

Without some type of controller How do you determine how much flow you are actually running through the UV. I want to use it for parasite control

 

[Quietman]

I use a gallon jug on the outlet of the flow and a stop watch and do math. I have a controller and still do that. Flow meters are not that accurate unless new and clean (and how long does that last) so hasn't been a priority of mine until I hear more positive reviews.

Guess I'm big on 'doing math' reading last couple posts. Good thing you didn't ask me about heaters.