anti-siphon questions - photos

[reeferdale]

OK, here some pics. I am stumped now on what is the best/correct way to plumb these inlets avoid a back siphon. I have three options
1. I have internal risers on all the bulkheads and they will have an anti-siphon hole drilled in them. It takes up room in the tank and I really do not like the look of all the PVC in the tank, even though I will cover most of it. I am sure this will work and would be safe.

this is the back of the tank. you can see all the PVC that has been added to the inside of the tank

this is the inside with all the PVC - keep in mind there are six of these inlets - a lot of junk to try to hide.
My other option is to do external siphon breaks. I like this idea (thanks to Jim, 'on the spot'). It will keep the inside of the tank clean. The issue is whether I can do just one break on the main inlet line, or if I need to do a break on each individual inlet line? I would hate to plumb this and find out the way I chose does not work. I would prefer to have just one break on the main pump line flowing into the tank. here are pics of the two options. I need some opinions on which one if either of these will even work.

single siphon break. Pipe is above water line and the tubing will be secured just below the water line

individual siphon breaks. Pipes can be raised above water line if needed for now the pipes are lower but each piece of tubing rises above the water line and will be secured just below the water line inside the tank.
The idea here is that once the water in the tanl drops below the flex tubing, theywill draw air into the main pump line into the tanl, and break the siphon. Once I get this tested and know that it works, I will also be adding a check valve to the pump return as a backup.

 

[VegasRick]

Its not just siphon you have to worry about but gravity. Gravity will probably cause the tanks to drain to the height of the bulkhead. I think you would be better off using those holes for a recirc pump. Maybe take one for the return but you will have to raise it to the top of the tank on the inside

 

[Reef Pets]

As stated above siphon will not be the issue but instead gravity will drain your tank into your sump. A closed recirculation loop would be best then you dont have to worry with siphon or gravity. Use a separate pump for your return.

 

[reeferdale]

As stated above siphon will not be the issue but instead gravity will drain your tank into your sump. A closed recirculation loop would be best then you dont have to worry with siphon or gravity. Use a separate pump for your return.

so if I were to raise the main 1 1/2" pipe from the pump to run along the top of the tank and feed the bulkheads from the top down, then I should not have any gravity issues, and the anti-siphon issues would be removed if I can just break the siphon with the airline intakes right?

I do not want a closed loop on this tank and I do not want to run >1 pump

 

[Reef Pets]

If you were to feed from the top down then gravity would not be an issue but its likely that you would still get siphon. But, one siphon break should take care of the issue.

 

[Troylee]

I would never use those for a drain.. You have a drain and return inside the overflow "that's safe" the rest should be plumbed to a pump as mentioned a "closed loop" I would hook them to a reeflo dart or hammer head and rock that tank!!!

 

[VegasRick]

I think it might work ok running the 1 1/2 along the top of the tank. Like stated above one siphon break should work, and instead of all those tubes for siphon break just T off the 1 1/2 with a half inch and turn it down into the tank ending right below water level. That would clean it up quite a bit.

 

[reeferdale]

so I have moved the plumbing to the top of the tank. This should eliminate any gravity feed issues, and I am going to try to use the single siphon break on the main discharge pipe. I can always mod this to add individual lines, as long as one of the lines introduces air into the pipe, then it should break the siphon. I like the idea of just using some 1/2" PVC instead of the flex tubing I now have, I will switch it to a hard plumbed 1/2" fitting. I will also change the fitting on the pump outlet to a Y fitting and I am going to use spaflex to connect it to the top manifold. I just need to build some support for the top header pipe, maybe some acrylic tubing just to add a little support.
Anyone else with feedback please let me know. I am going to wait till the weekend to glue this up.

top plumbing - back of tank

top plumbing back of tank angled

 

[reeferdale]

I would never use those for a drain.. You have a drain and return inside the overflow "that's safe" the rest should be plumbed to a pump as mentioned a "closed loop" I would hook them to a reeflo dart or hammer head and rock that tank!!!

I am not using them for a drain, these are all feed lines from my pump. The drain is the 3 stand pipes you see in the overflow box. I do not want a closed loop casue I am trying to use only 1 pump. I do have a couple big koralina that I plan to add to the tank on my apex. Feeding these bulkheads from my sump has turned out to be a real pain becasue of the location but I think I am real close to getting it right.

 

[Troylee]

The way you have it now will work great... Just need a single siphon break now should be easy...

 

[reeferdale]

The way you have it now will work great... Just need a single siphon break now should be easy...

yep, I got a great suggestion, I am going to add a Tee to the main header line and run some lockline just below the water surface, this will keep the surface agitated and work great as a siphon break, plus it is always adjustable if I need to!

forums are great

 

[Troylee]

Sounds like a man with a masterplan...1smile1 glad we could help...

 

[reeferdale]

ok, thanks to all who have helped. I am going to add a Tee to the left end of the main header pipe. From there I will add some lockline and have it discharge just below the surface. This will help to agitate the surface and also will act a siphon break one the water level falls below the lock line. If I need to, I can add more than one of these along the main header pipe, I may actually add 2 just in case one fails or gets plugged. Once I test this and see that it works, I still have a 1 1/2" check valve that will be the main line of defense. I am doing all this anti-siphon so that if the check valve ever fails I know that the tank can break the siphon on it's own.

thanks to all, I am going to glue this up over the weekend so I can fill it up and let it run for a week. Once I get all the kinks worked out and adjustments made, I am going to get the sump divided, add my skimmer and reactors, and add drain lines. Then I will be able to add salt and sand and let it run and cycle while I do the LED build. I am still hoping I can have something in the tank by the end of the year. Then all I have to do is the canopy and the front shelf.