This is the core equipment of the propagation system/frag tanks/quarantine. I am really please with how this system turned out as far as simplicity and flexibility.

Stands

These make quick (easy) aquarium stands.

They are steel racks that are 36x18x72 and can separate into two racks that are 36" tall. This will give me a total of four racks - 3 for the prop tanks and an extra for storage.

Each rack will apparently hold 4,000lbs so this should be plenty to hold the few hundred lb load that I will be putting on it. Being 36" x 18" should be perfect for the prop tanks plus some extra working room on each side.

These racks are about $60.00 each at the big orange box hardware store. The cool thing is that they split into two "aquarium stands" so you end up with a 36x18 stand that is about $30.00!

My tanks are actually about 3/4" wider than the racks so the tank frame would be sitting on the steel part of the rack and only supported on the back and front with no support on the sides. The other problem is the MDF wood shelves included with the racks are kinda flimsy being on about 3/8" thick . My solution so far was to cut some pieces of 1/2" plywood to go under the tanks to give better support (you can see the wood base in the pic below).

Additional support with 3/4 plywood

I also picked up a 14 gallon rubbermaid container for a temporary sump until my AGA 20H comes in. It will also come in handy for water changes later.

I also finished cleaning out the corner of the basement and set up the "stands". The middle will hold the sump underneath and the other two will serve as extra storage.

Stands with tanks in place

Plumbing
After looking at the prices of union valves in the hopes of making the plumbing removable it seems that it would be more cost effective to just replace part of the plubing again when I move the system.

If I make the runs of pipe a few inches longer under the bulkheads I will then be able to cut them and then repair the cut with a coupling after I move the tanks.

All of the return side of the system is ½" PVC with the exception of a short run of ½" ID vinyl tubing from the pump.

I turned the tanks around so I could get to the backs to install the bulkheads and measure and cut the pipe. Everything is just a "dry" fit right now so I can turn it back around and glue all the parts. The drains are 1" bulkheads with strainers that connect to 1" ID corrugated hose that simply runs to the sump.

Fitting the PVC from the back

Be sure to have plenty of ventilation and fans when working with PVC glue.  Each tanks return line from the pump has a ball valve so I can control the flow. The middle tank gets the most flow so by turning that valve down a bit I can balance the flow fairly well between the three tanks.

Ball valves for flow control and tank isolation

I then added tap water so I could do a wet test. First thing I noticed after turning the pump on (and having a brief "it's alive" Frankenstein moment  ) was that the flow is just not enough. At the same time the Quiet One 3000 at 780 GPH was probably going to be too much for the sump and the likely small skimmer that will be in the first section.

Flow... always either too much or not enough

What to do?

I am thinking of using a nice size diaphragm air pump and some airlifts to get the extra flow. I am also thinking that I will hook this extra air pump up to a battery back up system as part of my fail-safe. Airlifts seem to be the way that the greenhouse growers get the required levels of flow in the bigger systems - efficient and effective. I will also have to go down a notch on the return pump. Maybe to 500GPH? I am thinking that if I use anything larger I will probably have micro-bubbles getting pumped up from the sump into the tanks.

The temporary sump is a Rubbermaid 14G container. I never seem to have enough of these around so I picked up this one to use as a testing sump. I have used these containers for quarantine, curing live rock, water changes, etc. I am sure it will come in handy later.

Temporary Rubbermaid Sump

Next step is to build the real sump.

The Sump
Since this is a fairly small system I decided to use only a 20g aquarium and section it with baffles to create areas for the drains/skimmer, refugium and pump return.

The one thing I did wrong with this sump is I made the baffles to tall. I should have used 8

The finished sump makes this system pretty much ready to go. The one thing I did wrong with this sump is I made the baffles too tall. I wish I would have made them about 7-8" tall instead of 12". This would give me a lot more overflow volume for when the pumps are turned off. The water draining from the tanks above comes almost to the lip of the tank when the pumps go off!

Finished sump