Backyard Aquaponics
A place to discuss aquaponics

Can you explain the expansion joints you mention above. I have been thinking of something similar, but was just going to poor the foundation and then build with concrete block on top of that. Then seal it all up with fibromix. What is the purpose of the expansion joint, and what material is it?

Thanks
Mark

Firstly I must say that I have follwed the South African cement and concrete institutes guidlines for building reservoirs of brick and concrete blocks. They stipulate that reservoirs must be built from solid concrete blocks or cement bricks, not hollow 'breezeblocks' ever. The wall is built on top of a foundation which is floated smooth and then coated with a liberal layer of bitumen. this created a sliding joint for the wall. Then the floor is cast up to this wall with the expansion joint inbetween which is a foam material like a hiking matress foam. Available for concrete slab expansion joints. this alows the floor to expand and contract without pushing on the wall and cracking it. The floor and the wall and the foundation are all seperate elements able to move without damaging one another. I built a 50 000 litre reservoir using a single skin cement brick wall. The secret to this is that it must be round. Square tanks and pools require a much higher materials input for the equivalent volume. This is due to the round walls supporting themselves.

Texans (Houstonians even! Hi Mark!) can now find an excellent uncoupling membrane at the big box store Home Depot. "Ditra" by Schluter Systems. I have seen it there with my own eyes but can't remember if it was in Flooring or Building Materials. Usually it gets mortared to the floor underlayment and tiles get mortared to the upper "waffle" side, but it would work fine as an expansion joint for a Fanner StargateTM.
I buy it from tile-experts.com but you can see and feel it at the Home Depot.

Let's see, hijack over, back to the topic, uh...
I like how the holey twisty standpipe can also be used to nip off roots that venture into the drain!

Keep the pictures coming Brian! Great example of how solid construction standards, aesthetics and efficient function can come together on an affordable budget. I nominate for a sticky...

Phew... it's really silly season now. Have done little on the system and the dog ate my phones and camera cable so no new pics. I have put in some drainage pipes from the growbed to the proposed sump position. I am wondering what kind of fall I should have on the 50mm drain pipe as the less it is the less excavation I will need to do. I am thinking to build the sump from brick and going about 600 deep and then make it as big as it needs to be (Still a little fuzzy on that) to be a large sort of sunken growbed. Othersize a smaller duckweed pond for fish food. If Gravel growbed then it need to be bigger and it will be hard to work as it will be slightly sunken. If it is a duckweeed pond then I can scoop it out with a net and the pond can be smaller/cheaper.

The dog eating your phone and cable is not an acceptable excuse...

You could have opened the dog up... transferred the photos... then used the cable to sew the dog back up...

Please don't offer such a lame excuse again...

To sump or to Sump/growbed

Well if you Sump/growbed it needs to be equal/larger than all the other grow beds combined and you will probably want to work out a somewhat more sunken sump pump well where you can keep the gravel out and install the pump so it is easy to access and a bit lower than the rest of the bottom of the sump/bed to make the drainage a little better.

If you go regular sump pond, then you want it to be at least about 60% of the size of the grow beds. Figuring that the grow beds require about 50% of their volume to flood them with water and you want some extra amount of water so the pump doesn't run dry and perhaps enough depth below the normal low water level but above the pump sucking air level to install an automatic float top up valve.

On your comment about the sump being a duckweed pond. I've found that duckweed has some difficulty growing well in a tank where the water level fluctuates and there is water splashing in and stirring it up. Duckweed tends to like rather still water. Splashing tends to stir it up and some of it will get sucked through the pump. Fluctuating tank levels leaves much duckweed stuck to the sides to dry out and die.

If wishing to grow some duckweed, I would suggest working out a bed where the water can flow through gently and have the bed set up as constant height of water.

If you go with the gravel filled sump/growbed you get a much higher ratio of gravel to fish tank quite quickly. For instance, if the sump/bed is equal volume to the fish tank and the regular grow beds volume is equal to the fish tank, Tada= 2:1 Grow bed to fish tank. This layout would also allow excess flow from the fish tank to go directly to the sump bed instead of it all having to go through the other grow beds since the sump bed is a filter and will be able to handle some solids.

Granted, this whole sump bed idea is just kinda theory as I've never quite set up a system in this manner myself.

The insides of the growbeds are sealed and the drainage pipes are installed. It looks quite cool with its quad exhausts . Next to turn my attention to the tank and the overflow. and then to the sump. I am not looking forward to the digging...

Awesome looking system so far
We need more pics and an update

I am watching this thread very closely because I am moving back to Thailand in 2 weeks and (even before I saw this thread) I had decided brick/concrete/render ponds are the way to go there.

Your system is basically exactly how I have pictured my planned system.
My biggest worry is finding something to line the tanks with, I may ever resort to tiling the inside of the ponds, not sure yet.

Get that cable out of the dog and give us some updates

Dui

Thanks dui. Round brick ponds are fairly easy to build. I have used a bitumen emulsion to seal the ponds that is designed for koi ponds but tiles are a good idea that I never considered. I was given a 10000l plastic tank for the sump which is cracked at the outlet. It is now cut down to 3000l and being mended for free by my local roto moulder. This will form the sump. I still need a pump...

Very neat BF....

You do have a lot of digging still to do though.. Looks like it's fairly easy digging though, a bit like here in Perth, straight sand.

Test post

wow... amazing it worked!

Sorry guys. I have not been able to post anything for weeks due to some weird technical issue that seems to have cleared up all by itself.

So a quick update... I have had the sump tank leak fixed and done the dreaded digging bit. (actually I enlisted the help of two of the farm laborers). It went quite quickly and we got the sump tank in in a morning. so now I have all the tanks in place and the grow beds draining to the sump. I now need to get the overflow from the FT to the growbeds and get the pump hooked up from the sump to the FT. The cement tanks are all sealed and will be ready for water in 5 days time I have settled on a submersible pump capable of pushing 5500 lph which should be fine. will post pics soon.

here are the pics. Sadly the tank has gone wonky but I am going to need to cover it up for safety reasons. My stupid dog who loves to swim keeps jumping in there and then can't get out.