Sump upgrade with auto drip


Blue Tier VIP
MFK Member
Apr 22, 2006
Recently upgraded my sump for my 150g tank:

Here's the old sump. 40g breeder with a filter sock and 2 blocks of 4" poret foam (I like to keep things simple).

This sump has served me very well since I set the tank up over 4 years ago. However, I recently decided to put my whole system on an auto drip. I initially set it up with a DIY PVC overflow like the one here:
, but I found it ended up being pretty unreliable and losing siphon due to bubble slowly accumulating in the U tube and forming an air break. So I decided to replace it with a drilled sump, and also thought I'd go bigger to increase my water volume.

I got lucky with a craigslist find. An old reef sump. Dimensions are 48" X 24" X 18" so around 90g.

Tank was a mess when I brought it home. But a few hours with some vinegar and elbow grease cleaned it right up:

Connected up plumbing for my overflow and did a leak test:

Close up of the overflow. The water height in the tank is determined by the position of the T and hose barb on the external standpipe. I measured this to keep the water height right at 9", so half full, which gives me an operational water capacity of around 40g.

And here's the new sump in place. It was too big to fit through the normal openings, so I had to temporarily remove the center leg from the stand to get it in, which was a bit nerve wracking, but it all worked out.

I set up the new sump in pretty much the same way as my old sump, keeping things nice and simple. I wanted to reuse the same poret foam from my old setup, but it was only 18" wide, so in order to be able to keep it in place I used some sheets of matala mat as baffles. I bought one 24" X 40" and cut it down into 4 ~10" pieces, plus I threw in one extra old piece that I had sitting around. This gives me a lot more media than I used to have, and the matala baffles give me room to add more foam or filter pads in the future if I need.

I used one of the existing holes that had been drilled in the sump to make a PVC holder for a float valve to act as a safety shutoff for the drip line (I spliced this off of my water main and ran it through a pressure reducing valve and a 3 stage carbon block filter). An increase in water height of ~1-2" will lift the float valve and turn off the flow from the drip. Positioning the drip inlet just above the water surface has the added advantage of keeping things pretty quiet (I can barely hear the water dripping into the sump).

Overall I'm really happy with the upgrade. Water in the tank has been crystal clear and the auto drip has been great.


MFK Member
Feb 11, 2013
Twin cities
Nice work !!!

Out of curiosity, what happens if you remove the filter socks?

The poret foam website shows a sump with just the foam, no socks.