Anti Siphon Hole is making my overflow too loud!

+1 on this... i have never used a hole either on a return always kept the return nozzle just under the surface.

 

The key idea here is to have sufficient space in your sump/refug to account for a power outage. My LocLine spray bars are just below the water's surface as well.



Luna

 

Not needing a hole really depends on the surface area of your tank vs the size of your sump. My return lines are only about an inch under the surface too, but that one inch in my display tank is 30+ gallons Not enough room in my sump, so I run holes, that way it cuts out when I've only gained a few inches of water in the sump. I would not count on check valves, as they are notorious for getting clogged with calcium and failing. The simple holes are much safer.

 

Drill a hole in the bottom side of the loc-line and plug the one on the 90.

 

30 gallons per inch? How tall is your tank, 7"? (Looking at your signature it says 200 gallons so 30Gx7"=210 gallons).
Say its the average 24" high it would be more like 200/24=8.3 gallons per vertical inch not 30 gallons.

My tank is a 60" long x23" tall x 18" deep 100G and holds about 4.3 gallons per vertical inch.

If you don't have 8 or 10 gallons of freeboard in your sump you are asking for trouble drilled hole or not. I maintain over 8 gallons at all times in my 30G sump and only really need 4 but include a safety factor for peace of mind.

 

Thanks! I think I will go with this option. That way I won't have to remove my return tube to fill the hole and drill a new one. I'd have to remove my overflow just to get at my return because of the spacing of the holes they drilled in my tank. Either that or hire a contortionist to do the work for me! ;-)

My sump has enough capacity to handle the extra water in the event of a power outage.

Cheers!