Sump 101


What about my dynamite?
Re: what is everything i need for a sump

You will need.

Baffles x 4, all the same height and width. If your sump is glass, get them cut at a glass shop. Measure the inside of your sump tank, and reduce the measurement by 1/4". Transfer measurement to cardboard panel, make sure the cardboard panel fits. If it doesn't, cut more. Once it can fit with about 1/8th of an inch on each side, take the measurement to the shop and have glass ones made. Height should be 10" to 12". This will give you room to adjust the standing height of your skimmer's water level. Oh, and when you make your bubble trap, set the middle baffle about 2" higher than the other baffles, as illustrated below. You can set the height, and width of the baffle chambers with cd cases, dvd cases, or an old book. I used an iphone 4 box.

Silicone sealant for baffles. Make sure you get the kind that's safe for aquariums. You want 100% silicone sealant with absolutely NO mold additives. The sealant you want is translucent. If it's white, you got the wrong stuff. You can find it at a hardware store, but you can also find it at petco; they'll make you pay extra because it's 'for aquariums'. But at least you'll be 100% sure it's safe.

Hang-off back, (HOB), Overflow. Depending on the size of your tank, a single pipe, 300gph would be fine for a small to medium tank. A dual pipe, 800gph for larger. Get braided, clear hose from the hardware store, (and the appropriate PVC connections and hose barb), and test for leaks.

1/4" clear or 'airline' tubing. Pick up several feet of this. You will use it to start your overflow, acclimate fish, start other siphons, etc.

A return pump. Get a pump that's slightly under your overflow rating. This will insure that your display tank doesn't overflow; a stronger pump would pump more water into your display faster than the overflow can take out. However, you might have to get a larger pump than your overflow, IF, your return pipe is too long, or you've split part of the return to go back into the sump. Eheim's are great pumps but expensive; Tunze pumps are getting great reviews and are more affordable. If you're on a budget, danner mag drive pumps are super reliable and cheap. They're a bit louder, and transfer more heat into the water, but this won't affect anything assuming your heater is set correct.

A protein skimmer. This will go in the first chamber of your sump. This insures it gets the worst stuff, and that anything living in your refugium or other chambers will not get killed before being pumped back into your display. (pods.)

This is what I prefer; the refugium gets lower flow this way and is a more peaceful area for pods. Not shown: the intake pipe going into the skimmer area:


This is more common, but water flows through the refugium area as fast as the return pump is pumping out. This may cause some turbulence Not shown: skimmer in first chamber.



On your RETURN pipe, where it dumps into your Display Tank, just under the water level, make two or three holes in the pipe, as a siphon break. You see, when you have a power outage, or when you shut off your return pump, the weight of the water in the return pump will be pulled down by gravity, causing a REVERSE SIPHON; water will now empty out of your display tank through the return pipe, potentially overflowing your sump. Having these holes drilled in the pipe, will insure that air will break the siphon, causing the reverse siphon to stop. ALWAYS check these holes and make sure they're clean every week. You want at least two holes, just in case a snail or other animal happens to be covering one when the power goes out. The overflow, on the other hand, does not need a siphon break, as it will be kept in stasis. When the power comes back on to the return pump, the overflow will restart it's siphon, once the water level of the display tank rises above the overflow teeth in the tank.


There are other types of overflows, but this is usually the most common beginner setup. If you're not afraid of drilling glass, you can look into a bean style overflow, or glass-holes overflow.

Easiest yet, buy a reef ready tank with built in overflows.

It's a lot easier than it sounds.
Re: what is everything i need for a sump

Some other things:

When you have a sump, your display tank will ALWAYS appear full due to constant pressure; there is no need to worry about the water level dropping in the tank and looking ugly.

Instead, the water level will drop in the return chamber in the sump. This is what you will have to top off with freshwater (not saltwater!), every day. You will lose anywhere from 1 to several gallons a day in this chamber. When making your sump, make sure the return chamber is not too small. If you make a tiny return chamber, 1 gallon of evaporation can cause your pump to suck air and get damaged. Make sure your return chamber has enough room to hold 2 to 3 gallons worth of evaporation before the water level reaches the pump, just in case you forget. Also, this means you won't have to top off every few hours. It's best to keep it topped off as much as possible, (for water stability purposes), but it's nice knowing you have some insurance. Your next upgrade will be an Auto Top Off system, that will do this for you; then you can have a reserve tub, bucket, or tank of water with as much gallons as you please, giving you plenty of time to enjoy your tank without having to think about adding water all the time.

Having a sump also allows you to setup media reactors for coral supplementation. But that's another topic altogether.
And do I need a trim/rim around the sump to help enforce it? Is 1/8" thick glass ok for a 5 gal that I'm building?
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Trim around the top? I'm not sure what you mean by that.

You will need thicker pieces of glass than that, the glass tends to bow when it's that thin.
I was told by the glass shop that I would need like that black trim you see on some aquariums becuase the silicone itself isn't strong enough to hold together the glass with all the water pressure. He said the sump would eventually break apart
I meant the main 4 walls of the sump. The glass rep was telling me it that the silicone may not be enough to hold them up. Is this so?
Yes. You need the support around both the bottom and the top.

And unless you are building an odd shape you're better off buying a small tank and adding baffles on your own.
I ended up buying a 7 gallon glass aquarium. I will be adding baffles to it sometime within the next few weeks. My project has been on hold for awhile.
Which is the chamber that needs to hold at least 3 or more gallons of water at any given time due to evaporation? I'm looking at my plan again to finally build this thing. Is it where the water pump is located?