Draining Stagnant Water from UV Bypass

[Biokabe]

I have a UV system installed on my stand, a 25w Pentair unit. When my Reefer went down and I switched over to the new tank, I closed off the bypass to the UV system, and for simplicity sake just... never got around to opening it back up again and starting it up again. A big part of the reason was that I wanted to add a second pump to my sump just for the UV, giving it a dedicated pump with which to better control flow through it. I have that 95% done - the separate line is setup, the return is positioned, the pump is in the return chamber - but I haven't connected the whole new system to power and started it up again.

At some point I'd like to do that, but that water in the bypass has been sitting there, stagnant, for almost a year. No idea what condition it's in. Am I overthinking this (I have been known to overthink things), or do I need to figure out a way to drain that water out (and obviously replace the lamp and sleeve, they were already close to needing it) before I return the UV system to functionality?

 

[UncommonSense]

I have a UV system installed on my stand, a 25w Pentair unit. When my Reefer went down and I switched over to the new tank, I closed off the bypass to the UV system, and for simplicity sake just... never got around to opening it back up again and starting it up again. A big part of the reason was that I wanted to add a second pump to my sump just for the UV, giving it a dedicated pump with which to better control flow through it. I have that 95% done - the separate line is setup, the return is positioned, the pump is in the return chamber - but I haven't connected the whole new system to power and started it up again.

At some point I'd like to do that, but that water in the bypass has been sitting there, stagnant, for almost a year. No idea what condition it's in. Am I overthinking this (I have been known to overthink things), or do I need to figure out a way to drain that water out (and obviously replace the lamp and sleeve, they were already close to needing it) before I return the UV system to functionality?

So, the water in there is likely to to reek like rotten eggs… you’re wise to want to drain it out!

Is the return plumbing on unions so you can just disconnect it all and take it outside to blast out with a hose?

If not, the sterilizer itself should have unions… though, this will be a stinky mess entailing a drip tray and likely some spilling/airing out the house!

 

[get-salty]

sitting saltwater for a year.. yikes
get a 20gal tub, undo everything and throw it in and take it outside for a wash.

 

[exnisstech]

I would pull it and clean it. I left one off for a couple of weeks and it was some stinky stuff that came out. Fortunately it was a 180g so it didn't cause any problems.

 

[Biokabe]

Alright, so I wasn't overthinking it.

I think it's on unions, but even if not it's connected to the pump and return via flex rather than hard plumbing so it can be removed and cleaned out.

 

[KrisReef]

Alright, so I wasn't overthinking it.

I think it's on unions, but even if not it's connected to the pump and return via flex rather than hard plumbing so it can be removed and cleaned out.

If possible, move the pump to a fresh water source and pump the chamber with a dump bucket or a drain.

It’s going to be stagnant but it doesn’t hold much water to fuel a plague-load.

 

[UncommonSense]

Alright, so I wasn't overthinking it.

I did this with a canister filter once, years ago… a case of breaking down the tank it was on and setting it aside/forgetting about it…

When I finally remembered it existed months later, I cracked it open and cleaned it out… ALL of the ceramic media in it had disappeared (dissolved), and the filter sponges/ABS plastic filter media trays were oddly shrunken and warped…

This is to say, double-check the inside of the UV housing, and seals for any unusual wear!

 

[W31Olds]

Could you use a Python system to suck the Water out of the line? That worked for me a month ago.

 

[KrisReef]

I did this with a canister filter once, years ago… a case of breaking down the tank it was on and setting it aside/forgetting about it…

When I finally remembered it existed months later, I cracked it open and cleaned it out… ALL of the ceramic media in it had disappeared (dissolved), and the filter sponges/ABS plastic filter media trays were oddly shrunken and warped…

This is to say, double-check the inside of the UV housing, and seals for any unusual wear!

Interesting. Do you happen to recall the brand of ceramic media? I can see aragonite turning to mush in low pH but properly fired ceramics, I would not expect to disappear in an unmoving environment?

 

[UncommonSense]

Interesting. Do you happen to recall the brand of ceramic media? I can see aragonite turning to mush in low pH but properly fired ceramics, I would not expect to disappear in an unmoving environment?

It was a combo of Marineland ceramic cylinder media, and Seachem Matrix, if memory serves correctly!

 

[BryanM]

I would definitely remove and clean.

 

[Privateye]

I may be misunderstanding, but when you said the bypass was closed, do you mean this sort of a bypass? Usually "bypass" is used to describe water going around the UV instead of through it.

If so, then I wouldn't worry. Water is still flowing past it on the inlet and outlet side of the UV. There will be enough exchange that it shouldn't cause a problem.

If you mean that the bypass was opened and the valves to the UV were shut, then yes you could develop some hydrogen sulfide in the UV housing. If there was a lot of organic material in the unit then you may even see some parts stained black.

I've restarted a very dirty canister filter that sat for a week or two without flow. It certainly made the house smell bad, but the fish didn't seem affected. This was freshwater though - no corals.

Come to think of it, I have another canister filter in the garage that's been sitting with water for a year....It will definitely get a thorough cleaning (in the backyard) before I use it again.

 

[Biokabe]

I may be misunderstanding, but when you said the bypass was closed, do you mean this sort of a bypass? Usually "bypass" is used to describe water going around the UV instead of through it.

If so, then I wouldn't worry. Water is still flowing past it on the inlet and outlet side of the UV. There will be enough exchange that it shouldn't cause a problem.

If you mean that the bypass was opened and the valves to the UV were shut, then yes you could develop some hydrogen sulfide in the UV housing. If there was a lot of organic material in the unit then you may even see some parts stained black.

I've restarted a very dirty canister filter that sat for a week or two without flow. It certainly made the house smell bad, but the fish didn't seem affected. This was freshwater though - no corals.

Come to think of it, I have another canister filter in the garage that's been sitting with water for a year....It will definitely get a thorough cleaning (in the backyard) before I use it again.

It's closer to "valves to the UV were shut."

When I originally installed my UV system on my Reefer, it was a retrofit situation. I plumbed the feed line into the return pump, then it went through the UV system and through the sterilizer, then out the return line from the sterilizer and into the return line for the tank.

When I moved to the new tank, I took advantage of not having a tank on the stand to redo the plumbing on the UV system, giving it its own dedicated pump that runs water from the sump through the sterilizer and then back into the sump. When doing that, I disconnected it from all flow running into the sterilizer and flow coming out of it. So since moving to the new tank, no flow has gone into or out of the sterilizer and the entire plumbing apparatus around it. And for a variety of reasons, I just never got back around to getting it running again.

 

[KrisReef]

It was a combo of Marineland ceramic cylinder media, and Seachem Matrix, if memory serves correctly!

The scenario is an interesting question for RHF to discuss with regards to solubility and dissolution. @Randy Holmes-Farley, would you expect this kind of thing?