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Return flow question.

Srt4eric

Srt4eric

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I want to add a check valve onto my return line. To glue one in I'd have to take my sump off line for 24hrs. Can that be done safely?
 
Yes you can. Just make sure there's flow in your tank while it's offline.

As an aside, not sure why you'd want a check valve on your return line. They're worthless imo and you're better off without one. They're not something that you set up and forget since they need to be monitored, cleaned and maintenance regularly.

Your sump should be able to hold all the water that backflows from your return line, plus overflow, in the event that you lose power or if your check valve fails (this then goes back to the original point of why not to install one once again).

Old pic of the plumbing under the 87G. This is the max water level of the sump once the power was shut off and there was backflow from the RFG + overflow box.
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That's a good point @Ibn. Just another thing to clean. At least with a true union swing check disassembly would be easy. My sump can definitely hold all the water when I turn off the pump. I just don't like all the turbulence it creates when I turn it back on.
 
Thanks guy!!! That's awesome. I always figured if I can still smell the glue that I shouldn't put water through it. At work if I'm gluing pvc the longest I've waited was an hour and a half for 3" pipe before putting 85psi of water into it.
 
The tank I just plumbed we let sit for an hour or so then ran water in it with no ill effects as well. I would say go for it if you want the valve, but I don't have one on my display. I am happy enough with ball valves. Also, food for thought, I sometimes backflush my pump to clear the screen of algae or other debris that gets stuck, so there is some merit to no check valve.
 
As a counter view I love clear spa check value with double unions so they are easy to remove if your need to. The advantage to check values is almost zero flow back into the sump. I have on both my tanks and love them.

Not sure why you would need 24 hours to install one. An hour is more than enough time.
 
I always assume the glue would leach nasty stuff into water if not fully cured.

Now I know, and knowing is half the battle!!
 
Srt4eric said:
I always assume the glue would leach nasty stuff into water if not fully cured.

Now I know, and knowing is half the battle!!
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While that is a good assumption, I think that chemically, things are all bound up after that first hour, which is why we empirically don't see any harm from that. I would still run carbon after gluing anything just to be safe.
 
Srt4eric said:
Thanks guy!!! That's awesome. I always figured if I can still smell the glue that I shouldn't put water through it. At work if I'm gluing pvc the longest I've waited was an hour and a half for 3" pipe before putting 85psi of water into it.
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You are super cautious about your fish/corals being affected by residuals, but if it’s for human drinking water it’s fine? Lol

I’m the same way by the way. I‘m perfectly happy to drink lukewarm tap water but my fish get only the best multistage RODI and the finest salt at the perfect temp.
 
H2OPlayar said:
While that is a good assumption, I think that chemically, things are all bound up after that first hour, which is why we empirically don't see any harm from that. I would still run carbon after gluing anything just to be safe.
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I am going to treat it like after you build an engine. Ya know the break-in period where you use cheap oil and change after a few startups/cool downs.

I will use regular water then run it for 24 hrs and then dump it into my garden.
 
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