Greetings. I might acquire an acrylic 240 Gallon drilled tank with dual overflow. I went to look at it yesterday but the one thing that I noticed was with the overflows. There are 2...1 in each corner....the one on the right is a standard overflow design with the slits (opening to the overflow) on the top....but the one on the left has the slits on the botton where the substrate would be. I have never seen this design before and was curious if anyone here could fill me in on it. To me it seems to be a bad design for an overflow tank (I can see the entire tank draining during a power outage if it wasnt plumbed correctly) but also I planned on using sand for my substrate and it would just clog up or get sucked down. Am I missing something with this design? I am thinking about just closing off the bottom slits and cutting new ones on the top like a standard overflow would be. But I thought I would enlist your help before I even acquired this tank.
Question about a 240 Overflow tank....
- Thread starter malawimonster
- Start date
I didnt get a good look at the bulkhead fittings...but it looked to be a 1" There was also 2 return pipes in the middle of the tank...so I dont think the left side was a return....but again I havent seen this design and its not set up hence my confusion...
The second one probably has a pipe from the drain up to the waters surface. Water comes into the overflow through the bottom slits and rises to the top of that pipe then drains. If the pump stops you wouldn't drain the whole tank. Sometimes they have a double overflow so the outer overflow has the slits on the bottom and the inner overflow water spills over the top, works the same way as the pipe system I talked about above......
That makes sense...Ill double check that there is indeed a pipe in there. So this is a common design? I was trying to think of the advantages...since the openings would be covered by substrate that it wouldnt really filter in a lot of debris
this reminds me of the megaflow over flow thread. the design was prolly meant to use a durso pipe in that overflow with the bottom slits. it would cause a problem if you're using sand, i would just cover it up and block it off and do like you suggested and make teeth at the top.