Plumbing Help

[EvoReef]

125 gallon reef build progress: If you see anything that you think could better this system let me know. This is the first time playing with PVC. http://youtu.be/7149iSBUmK0

 

[EvoReef]

@melv can I drill into the bottom of that lock-line

 

[melev]

Yes, under the highest knuckle. 1/4" hole pointing straight down should be your goal. I like to drill two holes so if one is clogged or covered by a snail's foot, the other can still do its job.

 

[EvoReef]

Can I not drill here instead of drilling into my locline or is that to high?

 

[melev]

No (unless that spot is normally submerged), because then you will hear the water shooting out and hitting the water in your overflow. By drilling the hole half an inch (0.5") under the normal water level, it is fully submerged and silent. When the power goes out and water begins to siphon back through the locline to your sump, that area will become exposed after 1/2" exits the aquarium. That is when the hole will suck in air, make a slurping sound and break the siphon. No more water will drain.

 

[EvoReef]

Gotcha... thanks allot. I appreciate it.

 

[melev]

I really need to do an article / video about this topic.

 

[AZDesertRat]

I have an different opinion than Melev on the drilled holes. Drilled holes, just like check valves are a false sense of security and often fail when you need them most. The best form of backflow prevention known to man is a simple air gap. By this I mean place the Loc Line nozzles only that 1/2" or whatever below the normal operating level of the display so when the power goes off or the return pump is shut of, only that 1/2" or any other very easily calculated amount of water flows back to the sump before the siphon breaks when the return nozzles are exposed to atmosphere, an air gap. We all know water cannot jump uphill so it cannot be defeated, requires no cleaning or maintanance and you can sleep soundly at night whithout worries of a flood. Drilled holes plug with algae and get dirty or a snail parks over the hole, or when it is needed a small fish or anemone gets sucked up against it, or some floating foozen food etc. Same with check valves, it does not have to be a catastrophic leak, even a grain of sand will defeat a check valve and flood the sump before you get home and notice it. And what is to say you cleaned the holes last night and today there is a power outage and your anemone just happens to be next to the hole and gets sucked up? It can happen at any time no matter how much maintenance you do or don't do as the case may be. They fail.

If we use my display as an example, it is a 60" long 100G that is 18" front to back and my Loc Line returns are 3/4" below the surface. That equates to 3.5 gallons that flows back to the sump in a power outage before the air gap is created when the returns are exposed to atmosphere and the siphon breaks. To calculate the gallons that could potentially backflow it is L x H x however many inches depth divided by 231, in my case 3/4" or 0.75". So 60 x 18 x .75 = 810, 810/231= 3.5 gallons.

Since my sump is a 30G and I run it just less than 2/3 full since this is where the skimmer operates most efficiently I always have 10+ gallons of freeboard or spare room in it at all times so a flood isn't going to happen. This particular system is almost 11 years old now and never had any issues. You don't need holes as long as you amke sure you have sufficient room in your sump to contain whatever backflow you feel comfortable with. I could drop my Loc Lines to close to 2.5" deep and still contain any backflow which is a good cushion.

 

[EvoReef]

@AZ you are absolutely right. I am going to go with you on this one. This is the same thing that my brother in law told me to do.

 

[StikHedRon]

+1 with AZ also. I would bring your drains all the down into your socks so they don't splatter every where

 

[melev]

Most people want to point their locline into the reef to hit certain spots. If you plan to keep the surface agitated exclusively, his system is good choice. Doing the math to determine what the sump can hold during a power outage is always wise. For example, my returns are 3" under the surface of my 400g reef, but I have a massive sump that can easily hold that much water. That being said, when power is restored the skimmer will turn on as well as anything else electric and may overflow because it is standing in too much water for the first two minutes. Something else to be considered.

 

[AZDesertRat]

Is your skimmer internal or external? Does it have a a skimmer cup overflow reservoir or jug if it is external?
There are always exceptions but rarely does an air gap not make sense. Keep it simple KISS. Everyone is insisting on dual overflows and complicated plumbing when simple works as well if not better when properly though out.

 

[EvoReef]

Skimmer will be in sump.

 

[AZDesertRat]

If the skimmer overflows it goes back in the sump where it originated. Not the best of situations since the skimmate in the cup is concentrated but no big deal since the start up skimmate is going to be mostly water and not organics. If the skimmer is external it could be an issue until things settle down unless you have a place the skimmate can collect when the cup gets full, a good idea even with an internal skimmer and easy to do. A drilled hole in the skimmer cup, some tubing and a milk jug works well.

 

[EvoReef]

I gotcha.

 

[melev]

You can do whatever you like. Both methods are proven and work very well. I run every tank I've ever set up with an anti siphon hole or two, and have never had a sump overflow in my home. Incidentally, the anti siphon holes have never clogged, although I always recommend to others that they should clean them out once a month as a precaution.

I have my skimmer in sump running to a waste collector externally. Even if my skimmer attempts to overflow, once the collector is full the skimmer's pump is powered down to stop any further export. This is especially useful when I'm out of town so the tank sitter doesn't have a disastrous mess to clean up.

 

[AZDesertRat]

Marc I like the skimmer overflow shutoff idea. Do you use a float switch or? Any pics on your site?

 

[melev]

Marc I like the skimmer overflow shutoff idea. Do you use a float switch or? Any pics on your site?

When I first set it up on a trial basis, this blog explains it: When full, shut the skimmer down... - Blogs - Reef Addicts

Eight months later, I set up the official version prior to leaving town for MACNA: Ramping up for my MACNA trip - Blogs - Reef Addicts

I haven't had to do anything further. It works exactly as hoped, and my only regret was not doing it sooner. All those years of sponging everything clean after it turned into a volcano... Oh well, it's been so nice ever since.