Bad over sight snowballs to big problem

[LostMind]

I say use the drilled holes for a closed loop (extra circulation is good!) and put the sump returns over the back

[Dale D]

Maybe I don't understand the set up correctly. Someone draw me a picture.

Is the output of the returns 6" below the water surface?

If it is then putting a T with a cap and a hole in it will not stop the tank from back syphoning.

It will work more like a durso and gravity will push the water level in the tank down until it is below the return and that will stop the flow of water out of the tank.

Unless I am not understanding the setup correctly.

If that is the case then ignore everything I said and I will go back to sleep.

[Delphinus]

Originally Posted by Dale D

It will work more like a durso and gravity will push the water level in the tank down until it is below the return and that will stop the flow of water out of the tank.

Unless I am not understanding the setup correctly.

Ohhh dear. I think you're right.

Wow, how did I miss that.

Um .. yeah Jason, I'm sorry but Dale's right. I clearly didn't have enough coooffffeeee after 4 hours of sleep last night.

A T won't work at all. All the water will need to come all the way up, and then back down again in order for a hole to service as a siphon break. As long as you have this looped up over the top of the desired water surface, I think it will work (it will be the same as if it looped over the top of the tank wall).

I think it's that (and still have to figure out a way to deal with the water coming out the hole when the pump is turned on), or, use the drilled holes for a closed loop.

Man alive ... do I ever feel dumb. Sorry man.

[Jason McK]

Ya Dale after much thought I kinda thought of that as well.
The only way that would work is if the return line came up above the water level first. and the "T" was placed above the water line.
Some other suggestions I've had have been
true union check Valve (that way I could clean it)
mechanical valve with the no power or default position closed.

I'm sorta leaning back to the Check Valve, If I could clean it and get one of very high quality it may just do for my purposes.


now to find a local source
http://www.marinedepot.com/aquarium_...tings_2.asp#cv
J

[Dale D]

Personally I'd be kind of leary of using a check valve. Any of the ones I have ever seen on systems have all failed after they have been in use for awhile. There's just so much stuff that can grow in the plumbing of a saltwater system and foul them up.

A union check valve that you could take apart and clean would be better as long as you are good about cleaning it on a regular basis.

I think I would use the returns for a closed loop and put a return from the sump over the back with a syphon break on it. Then you would have even more flow, and less to worry about going wrong.

[Jason McK]

Ya, I think I will bring the return lines above the water line and "T" it. Or drill another hole and make it a closed loop.

Oh well I tryed.

J

[TANGOMAN]

Actually, I knew all along the T wouldn't work... , that's why I advised against gluing anything initially. . I'm sure Tony knew that as well, hence he suggested you do this when no one else was around...
Oooops. Once again Tony and I battle it out for the status of "the village idiot".
Definately stay away from a check valve ! They require maintenance and anything that is difficult to access get's put off for "another day"... It's just human nature. When I used one, maintenance was put off for "many days". Well o.k, many years...see my post titled,"thank god for shop-vacs..." .
You could use a couple of 90's to bring the outlet to the surface level but that would signifficantly reduce your flow... . Cap the bulkheads and go over the back. You can incorporate a closed loop in the future...

[Jason McK]

Despite everyones warnings I have proceeded with a true union Check Valve. Feel free to say I told you so in a couple of months.
My reasons were simple, My original design was to keep it clean and simple. This does that.
My returns are all 3/4" so I went with a 1" valve that way the valve itself it 3/4 inch and this will aid in the flow restriction department. It is fully cleanable as it come apart completely. I have heeded all warnings and will expect a flood if the power does go out. I am putting a ball valve above it so if I'm home and the power goes out all I have to do is shut the ball valve. but in the 2 years I've lived here the we have never had a power failure.

I will ensure that if/when the Valve fails I will post so you can all laugh and say I told you so

Thanks for all your help

Jason

[Delphinus]

Well, it's conceivable you'll have no problems at all either, so who knows. It's your tank and if you think you'll be happy with that arrangement then that's really all that matters.

One parting thought though, it's not so much the diameter of the pipe that is causing the pressure loss, instead it's the spring that's pushing the flapper valve back (so that in the event of a loss of pressure, it's closing back and hopefully creating that seal). Also watch out for that spring, I don't know what they're made of, but since it's in saltwater watch out for corrosion. Luckily the unions will make it easy to periodically inspect for that.

How come you don't like the idea of a closed loop? Just curious.. If it were me that's probably what I would have looked at.

And .. not that it matters now but another idea might have been to go with loc-line and bring the end of the nozzle up closer to the water surface. Would help with surface agitation and if the nozzle was high enough then the water surface wouldn't have far to drop in a power-off situation.

But anyhow .. anything that works in the end is good enough. Good luck!

[Jason McK]

hey Tony. There were a few reasons I din
t want to go with a closed loop the biggest being it's only a 40G tank that is going to house mainly LPS and softies. I don't think I will need the flow. Also I would have to drill another hole and I have it too far along to do that. Also the Check Valve I purchased doesn't have a flap. It's a ball type so it's easier to clean.

What else, Matt Rogers @ 3reef.com ran a check valve for many years with out any problems. So he helped convince me it would work.
Everyones suggestions were great and if this even tries to fail I will modify the tank with any of the great suggestions.

I'll post picks when the plumbing is complete.

J