Now that I had a good idea what a sump was for I was ready to design and build my own.

I decided I wanted a wet sump with a refugium that could double as an isolation tank for aggressive fish.   Given the limited width of my stand I decided a 30 gallon long with a secondary refugium tank would work best for my set up.

Here is my initial design.   The plan was to have the durso overflow from the main tank drain into 2 filter socks.  I would have a bypass on the drain into the refugium and use a gate valve to control the flow.  Based on my research,  it is best to have a reduced flow in the refugium.  Closing the gate valve slightly would give me less flow than the rest of the sump.

In the event of a power outage,  I am guessing the top 2″ in of the tank will siphon back to the sump.  This will depend on where your pump return lines are, but 2″ is probably a good guess.  Plus the amount of water in the lines.  Given all of this I have allowed for 13 gallons of back flow in the event of a power outage.  This will be tested when I finally install the sump.

http://www.calculatorsoup.com/calculators/construction/tank.php

You can use this web page to help calculate your total back flow.  Enter the overall length and width plus your estimated water drop.

I purchased a 30 Gallon long and had to wait a week for it to arrive.  In the mean time I found a 10 Gallon tank on Kijiji I could use for the refugium.   It was a standard 10 Gallon with no holes drilled in it.  Based on my my design I would need a hole in the side of the tank for and overflow into the sump.    Time to learn something new.  I have never drilled a hole in glass before.  First time for everything I guess.   I picked up a diamond coated bit from home hardware.  Always love an excuse for more tools.  I will go into more detail on another post about actually drilling the tank, for now, I will stick to the sump.

After about a week and half, the new tank arrived and was ready to be picked up.   With the new tank home I could measure for the new pieces of glass I was going to use for the baffles in the tank.   The baffles should be about 1/8″-1/4″ smaller than the width the inside dimension of the tank.  This will allow you to install them easily without putting any pressure on the sides of the glass.  This is very important, any stress on the glass could cause a crack.  If the baffles do not slide easily into place, do not force them.  Either have them re-cut, or sand the edges down till they fit.

I had everything I needed to assemble the sump.

1) 10G refugium with hole drilled
2) 30G long glass tank
3) 5pcs of glass pre-cut by local glass shop
4) 1pc of Plexiglass for Sock Holder
5) 1 Tube silicone
6) 2 Filter socks

I used green painters tape to measure out the chambers and locate the baffles where I wanted them.   I started at the bubble trap with the middle piece first.  I used little wood pieces to hold the glass baffle off the bottom of the tank and clamps to hold the baffle level as seen below.

       

Here is where I made my first mistake.  I was too impatient and did not let the silicon on this piece set before I tried to add another baffle.  This was not a good idea.  The added weight of another piece of glass caused the whole thing to shift.  The silicone was everywhere. I had to pull it all apart, clean the tank and start over again.

I repeated the same process, but let the silicone set before adding the other baffles. I used 1″ x 2″ wood to space the baffles and slide clamps to hold them in place while the silicon set. With the bubble trap baffles in place time to install the filter sock holder.

I used the same technique to install the filter sock holder.   For the holder itself, I used the piece  of plexiglass so I could drill two 4″ holes in it to hold the socks in place.  I was concerned about drilling such large holes in such a small piece of glass.

With all the baffles in place time to leave it overnight to allow all the silicon to fully cure.

Complete tank with the socks in place.  Time for the water test.

It holds approximately 16 Gallons when full and the bubble trap appears to do a good job at preventing the bubbles from entering the return chamber.

Here is the sump and the refugium in the stand.

Overall I am happy with how the sump turned out.   A few mistakes, but in the end I have a sump that costs less than half what one would cost from my local fish store.