DIY sump/refugium and PVC overflow

I've been getting nitrate readings in my saltwater tank (and it's always nice to have a larger volume of water) so I decided I needed a refugium with some chaeto. I designed my stand to be able to hold a 10 gallon sump so that's what I used. Also, since the tank is already set up, instead of drilling the tank I put together pvc for the overflow system.

Here's the stand with the empty sump:


I chose my overflow design based on dozens of threads that I looked through of other pvc overflows that have worked. I cut everything down to size, made sure it fit properly, primed/cemented it together and then spraypainted it black using Krylon Fusion.

Side that sits in the tank:


Other side:


Sump setup with live rock, sand, chaeto, baffles (9" tall) return pump (Maxi-Jet 1200) and work lamp (26W CFL bulb):


Top of overflow:


Front view:


Side view:


Instead of using PVC for the return back into the tank, I used vinyl tubing that connects to a directional U-tube so it looks a bit more professional. The check valve is required to prime the system for the first time (and then it should hold it's prime thereafter) but for peace of mind I connected it to the venturI collar in the return pump so that there should never be any air sitting at the top of that bend to break the siphon. Even before doing that, I turned off the pump and restarted it several times and the overflow always kept its siphon. After shutting down the pump, there was also plenty of room left in the sump for the water to drain down without overflowing. So pretty much, the system won't have any problems dealing with a power outtage. The water level in my return chamber is lower than I'd like right now because if the overflow did fail for whatever reason, I don't want the display tank to overfill. I may cut the inlet tube another 1/2" down to allow for another 2.5" of water in the return chamber. I'm also looking into using one of those float switches used in ATOs except in reverse so that the pump would automatically shut off if the water level falls too low. After doing that, I'd feel fairly confident that no matter what happens, my system won't flood. The only way it would is if both the overflow and the float switch fail at the same time. Although I understand that it would be possible, I doubt with proper maintenance that it would actually happen.


Check out the rest of the build and leave some comments .

 

Oh wow! Another great job!

Ken

 

Thanks again Ken

 

Id like to use a sump when I get a bigger tank, except What if the pump fails?

 

If the pump fails, all of the water above the inlet drains into the sump (which is why you don't fill the sump all the way). Then when the pump starts back up, the overflow keeps its siphon and starts back up also. I've tested it out several times and haven't had any problems.

 

my sump is completly different, its based on the pump, not the overflow, so when pwr goes out no more water goes into the above tank, and the overflow is built in such a way that when pump fails, water line goes down about 1/4" (in a 75g) and stops, I just have to check every now and again that the overflow stays clean and does not get obstructed.

there are quite a few ways to make the overflow and pump, and I havn't seen two that are alike yet...

in fact, i've been looking at the overflow you made, and i'm not quite sure how it works... reminds me of a pretzel though... haha

 

I get it..

So where your pipe is that siphons the water down, its designed soe that the water level can only go so much below what it is normally,

But if the overflow is blocked, wouldn't the tank above get flooded and the pump, after not being in enough water, blow?

 

I get it..

So where your pipe is that siphons the water down, its designed soe that the water level can only go so much below what it is normally,

But if the overflow is blocked, wouldn't the tank above get flooded and the pump, after not being in enough water, blow?

I don't mean to steal this thread, but yes.

here is a pic of my overflow, I have (7) 1/2" siphons to drain to the sump, but I only need 5 to work to keep up to the pump.
the smaller tube is allowing air into the tube going to my sump, to decrease the sound

 

I have just looked it up on google and the skimmer, I think, is one of the most important parts...

 

my sump is completly different, its based on the pump, not the overflow, so when pwr goes out no more water goes into the above tank, and the overflow is built in such a way that when pump fails, water line goes down about 1/4" (in a 75g) and stops, I just have to check every now and again that the overflow stays clean and does not get obstructed.

there are quite a few ways to make the overflow and pump, and I havn't seen two that are alike yet...

in fact, i've been looking at the overflow you made, and i'm not quite sure how it works... reminds me of a pretzel though... haha

I don't understand why you claim that my sump is designed so differently (I don't know how your sump was designed so I'd like some explanation). If the power goes out, nobody's pump is going to send more water into the display tank. And everybody's water level will drop to a certain point to which it stops. I would hope that your sump was designed for BOTH the pump AND the overflow or you may have a major problem down the line.

I get it..

So where your pipe is that siphons the water down, its designed soe that the water level can only go so much below what it is normally,

But if the overflow is blocked, wouldn't the tank above get flooded and the pump, after not being in enough water, blow?

Not necessarily. My sump and overflow are designed so that if the overflow fails, the display tank will handle the water in the sump's return chamber without flooding. Right now, the pump would fail but that's much better than a flooded tank. I plan on installing a float valve that will shut off the pump if the water level in the return chamber gets too low which will solve that problem.

 

I have just looked it up on google and the skimmer, I think, is one of the most important parts...

Please elaborate...

 

I don't understand why you claim that my sump is designed so differently (I don't know how your sump was designed so I'd like some explanation). If the power goes out, nobody's pump is going to send more water into the display tank. And everybody's water level will drop to a certain point to which it stops. I would hope that your sump was designed for BOTH the pump AND the overflow or you may have a major problem down the line.

after reading your post again, I would have to agree, I guess I just missed something...

my sump is based off of this site

two small tanks, one inside and one outside the tank, a constant siphon between the two (mine has 7) and the tube going to the sump comes up thru the bottom of the outside tank sits higher then the bottom of the inside tank, therefore never losing the siphon.

 

I think I may so an overflow like yours. That is way easier/less risky than drilling the tank and the only reason I wanted to do that was I didn't want one of the acrylic overflows hanging on my tank

 

I think I may so an overflow like yours. That is way easier/less risky than drilling the tank and the only reason I wanted to do that was I didn't want one of the acrylic overflows hanging on my tank

Honestly, if your tank isn't set up yet, I'd look into getting your tank drilled. The fish store near me drills the tank for free if you buy the tank from them. That way you don't need to worry if something goes wrong and the tank breaks because they'll just do it again. I went this route because my tank was already running. For the first week, I only ran the sump while I was home because I was freaking out that something would go wrong. After tweaking the system and knowing that if either the pump or the overflow fails, I won't have any flooding, I run it 24 hours a day now. But I almost flooded my display tank the first time I made the overflow fail (on purpose for testing). I haven't had any problems with the overflow losing its siphon yet but it's still on my mind. At least now, if the overflow did lose its siphon, my display tank could handle all of the water from my sump's return chamber and I'd just end up losing my pump after it runs dry (which I may try to prevent by using a float switch that would shut off the pump when the water level dropped to a certain level).

 

Alright, I am making myself one of these when I get a saltwater.

 

I will also suggest having ago at drilling a hole yourself. I picked up a diamond drill bit for 20 dollars and it's been used for 3 holes in glass and one through plastic (normal drill was being a best through plastic). I think I could likely get another 3 holes easily enough.. so that's about 3 dollars a hole.

Now with the tank I'm setting up, siphons just aren't a concern.

 

Welcome to FishLore djdover

I definitely recommend drilling the tank whenever possible. It'll save you from all the concern of a siphon break. I'm definitely doing that on my next Saltwater tank before I set it up (although I'd probably either get a tank that's pre-drilled or have the LFS drill it for me because I wouldn't have the nerve to do it myself).

The overflow I made is great if your tank is already running and you don't want to take it apart to drill. I'm very satisfied with it though because in worst case scenario (overflow fails), all that would happen is my pump would run dry and I'd need to buy a new one (until I get a float switch to take care of that problem).

 

Thanks for the welcome, I'd love your input on my tank I'm setting up. Actually using a sump for a freshwater tank and drilled the holes for it..



Comments highly appreciated. Yours looks great.