After figuring out what design and layout I wanted, I made a scale drawing of the sump. I then made a cut sheet with a layout that wasted the least amount of acrylic. My design uses 1/4" or .236" thick cellcast acrylic sheet. There are several types of acrylic sheeting. Extruded and Cellcast are the main types used in aquariums. Extruded (usually has a blue film protector) is cheaper but is not as strong as cellcast (usually has a paper protector). Extruded is great for small pieces but is not recommended for tank heights over 12". Length to height ratio across a given area is also a factor here, but a 12" max height is a good standard. Cellcast acrylic height recommendations are basically: 1/4" thick up to 12", 3/8" up to 18", 1/2" up to 24" and so on. You can find plenty of info about thickness online. This sump is 22-1/2" tall and will handle being totally filled with water. However, most of the tank only has around 12" of water in it during normal use. Also, due to the design, there is no unbraced span greater than 16", and even that piece (the wall of the refugium) is offset by some water on the other side. Now, from the cut sheet I figured I needed: (1) 96" x 48" x 1/4" sheet, (1) 48" x 48" x 1/4" sheet, and one 24" x 24" x 3/8" sheet to build my sump. I ordered and picked up the acrylic from my local plastic supplier ( you might want to order glue at this time also, see my materials page for all the tools and products used). I also ordered some 1/8" sheet which I will be using to make the skimmer boxes inside the tank. After receiving the plastic, I followed my cut sheet and began cutting all the pieces. Make sure your cut sheet leaves extra room for the saw blade, and about 1/16" all around for routing. Cutting and routing is where a good shop vac comes in handy! This stuff is messy. It smells like a nail salon when you are cutting or routing, and statically sticks to everything. It's also amazing how 1-1/2 sheets of it shrink into a small stack when you are done. After cutting and cleaning, I routed every piece to exact dimensions. However, the ends of the front and back were left unrouted. The top ends were routed and the inside hole was rough cut, but the sides were left alone. The bottom was also left unrouted. I took one thick pass first which left between .010" - .030" or about 1/32". I then made a thin finishing pass. Try to be as exact as possible here. I was able to maintain between .005" - .010" tolerance on everything using a set of calipers to set my routing guide. But, it does not have to be this exact as the glue can shrink it more than that. Just making sure the pieces are square and have good edges is fine. Now its clean up time!

 After cutting and routing was done. I started gluing all the pieces together. I use the capillary and pin method and Weld-On #3 with a hypo-25 bottle. I found the syringe too hard to squeeze and control flow. Also, if the hypo bottle was too full it dripped easily where I didn't want glue! I found a quarter-full bottle works best. For pins you can use any fine wire from trash bag ties to regular straight pins. I prefer a wire used on a wire EDM machine. It is .010" thick. I found that thinner wire works best and leaves a cleaner joint with less squeeze out on the edges.  I also bend my wires up away from the flat surface. This keeps the glue from soaking around the pins and leaving pin marks beside the joint. Using water thin glue and the capillary method, all gluing must be done horizontal. This needs to be considered when designing and before gluing. My design had to be glued into small assemblies first. Then glued to the front, and allowed to dry. Then it was flipped up on end (or side) to glue in between the assemblies. So, plan your glue order before you start gluing.

 For easy understanding "left" and "right" are established when looking at the front of the sump. As for names, I call any piece running the length of the sump a divider. Pieces running across the width I call walls, or right and left sides for the two ends. Then we have the bottoms of certain sections that are named by their section. And finally, we have baffles. If you need to, look at the sump diagram section which has names and dimensions of each piece. OK?

First, I glued the waterfall baffles to the return divider. Make sure your pieces are square and the ends are flush with the piece you are gluing to.

Second, I glued the refugium divider to the refugium bottom.

Next, I glued the CO2 section bottom to the right side bio ball divider.

Then, the auto top off section bottom was glued to the left side bio ball divider, and all three pieces were allowed to cure for several hours.

After drying, the refugium bottom & divider were glued to the refugium left side wall.

The CO2 section bottom & right side bio ball divider was then glued to the sump right side end.

Next, the auto top off bottom & left side bio ball divider were glued to the sump left side end, and all pieces were allowed to cure.

After all three pieces cured several hours, the refugium bottom & divider were glued to the refugium right side wall.

 

The auto top off bottom & leftside bio ball divider were then glued to their right side wall, and all pieces were allowed to cure overnight.

Now, I have section assemblies. First, the refugium assembly left side wall was routed out between the bottom and the divider, leaving only a then strip flush with the divider. Second, the refugium right side wall was routed 1" up from the bottom edge in front of the divider creating a bubble trap out of the right side wall.

Next, I routed the left side bio ball assembly's right side wall to match the bubble trap on the opposite side. After cleaning up the router mess, I glued the refugium assembly to the front leaving enough space to the right for the bio ball assembly. The refugium assembly sets the squareness and placement of the other assemblies so I took extra time to make sure it was in exactly the right place.

 Then, the right side bio ball assembly was glued to the front.

Notice that the two assemblies have not been glued together yet, and that there is plenty of flex in the front sheet to allow pins to be used in between them later.

The return assembly was glued in next.

 Then, the left side bio ball assembly was glued in place, and all pieces left to cure overnight.

I then removed the film in between the sections, leaving only the outside film, and  then flipped it on one end. I glued the right edge of the return assembly to the refugium left side wall. I then let it cure for several hours. Next, I flipped it on the other end and glued the left edge of the return assembly to the left side bio ball assembly right side wall. Then, I glued the CO2 bottom & right side bio ball divider to the refugium right side wall. This connects all the assemblies together. It was then left overnight to cure.

 It was now time to glue the back into place. I glued it in sections to make it a little easier. Since the return assembly does not glue to the back, I glued the right side bioball section and the refugium section on to the back in one step. Then, I glued the left side bioball section separately. After curing overnight, the front and back ends were then flush routed. I placed two layers of tape where the router bearing glides on the acrylic and made a first pass. Then, I removed the tape and did a final finish pass. This made for very nice edges. When routing the final pass, I let the bearing come into contact with the corner first. This stops the bearing on the corner and prevents scratching on the outside acrylic surface.

 After cleaning up the the router mess, I decided to go ahead and drill the bulkhead holes in the bottom of the refugium.

 I then cleaned up the mess AGAIN! Next, I positioned the entire assembly on the bottom sheet with all the pins in the right places. I needed an extra hand and a stool during this step. So, while I was applying the glue, my brother came in behind me and removed the pins. The bottom was left to cure for several hours.

 I set the top on saw horses with support boards laid out in a box that was the same size as the top.  Because the top does not go all the way to the ends and overlap, I needed to glue the top from the inside.  So, reaching up into the inside from in between the saw horses I glued the top into place. It was then allowed to cure overnight.

The next day I routed the outside of the top and bottom using the same tape method as above. I then clamped router guides and stops around the top, and routed its inside edge.

 Next, I removed the top film and cleaned the entire sump. Following cleanup, I used 1/2" wide drop strips left over from routing and cut them to fit inside the bio ball sections. The sump was flipped on its ends and the strips were glued into place. These strips support the egg crate for the bio balls.

  The last pieces I made were the bio ball covers. They were made using 3/8" thick sheet with the edges and center strips routed down an 1/8". This allows the bottom 1/8" to insert into the top of the bio ball sections, and leaves 1/4" above which sits flush with the top. This also keeps water from seeping out the top seams because of the inset section.

The sump was then cleaned and allowed to fully cure for three days before water testing. During this time, I installed the plumbing and other hardware. (more info on this part can be found in the other sections)

  FINALLY ALL FINISHED!!!