existing holes

[jfdoutney]

I posted a little while ago about acquring a 75 gal acrylic tank and I've been reading and researching everything I could in between work, kids activities and love life. Sometimes I take a little while to catch on to things and then they just hit me.

The tank I got has three holes drilled into it, one on the left and two side by side on the right. This tank was part of a fish stores display and had been plumbed with about 30 other tanks, all hooked up to a common filter.

My long winded question is this; can I use the twin holes as a surface drain, one going to the skimmer and one to the refugium, and the lone hole as the return? I see that the usual method is to drill the bottom and build a box around it with a tube at the surface for skimming.

 

[Reefn'_Dude]

I assume these holes are near the top?

You would be able to use the holes with bulkheads and the proper plumbing for the described result, however, you need to be careful how you plumb it to allow for a power outage. Make sure your setup only drains what the sump can hold before your siphon's break otherwise you'll end up with flooding.

 

[kraze3]

Even if the holes are plumbed lower you can just run a piece of pvc up to the surface with an elbow down. Your plan should work fine.

 

[jfdoutney]

I'm going to use a 55gal for the sump, so I'll make sure I leave enough space for the tank to drain if there is a PF. I wasn't sure what the benefits/ drawbacks were for a side top drain as opposed to a bottom drain. Thanks for the reply!

 

[Reefn'_Dude]

It's not so much the bottom drain as it is seperationg the drain section from the main tank. the advantage to a water-proof baffel seperating the display from the drain is the amount of room you need to leave in your sump for PF drainage.

Set properly, a Durso behind a baffle will be a silent drain, and when the power cuts, the only water that drains into the sump (assuming you have put siphon brakes into all of your in display tubing) is what is in the pipes, and what is above the baffle edges in the display. Than all that drains from behind the baffle is down to the bottom of the horizontal section of the durso pipe.


This maximizes your sump space by minimizing what leaves the main tank in an emergency.

 

[MrMoses]

just use a one way valve to keep it from syphoning .

 

[kraze3]

"One way valves" or check valves are not very reliable. They can work when clean and new but they will quickly accumulate gunk and they can fail. When setting your tank up make a mark on the sump where your water line is. Kill the power and make a new mark to see how much drains down. By using the volume calculator you can then determine how much water you can have in your sump leaving extra room for the siphon down. Another way to prevent alot from flooding the sump is to use locline on the return. Shape it up towards the water surface then point it down where you want it to go. Drill a very small hold in the locline just below the waters surface. In the even of a power failure that hole will suck in air breaking the siphon.