500 ltr plywood tank project

[David R]

Good work!!

[Shilo]

Glass arrived so siliconed it in today. Wasn't as nerve wrecking as I thought it would be and went well with no gaps (plywood edges are exposed because the brace is removed). Hopefully I should be able to do a water test next week once the silicone has cured. Also took the opportunity to silicone some gutter guard over the weir to stop any fish enjoying a hydro-slide ride .

Other bit of progress was the sump drain. I will be trickling 25 litres of new water per day into the sump as part of the automatic water change but that of course means 25 litres of old water has to be removed. The sump has a stand pipe in it (not shown in pic) to set the water level and I added a cheap irrigation tap so I can adjust the flow. If I had it open, during power outages the sump will fill and the water will pour out of this outlet leaving only what's below the standpipe. This means the pump will run dry before the tanks overflow kicks in, the tap allows me to control how fast the water exits the sump and it should give me a good 8 hours to close it completely before levels get too low.

The second upright on the waste pipe is for the bulk water change which will come directly from the tank (should allow me to easily do a 50-75% water change if needed). The waste pipe heads under the house and into a spouting downpipe thus a soak hole.

Edited September 6, 2015 by Shilo

[David R]

Interesting set up, it has often vexed me how to have an open drain for an automated system without having it "accidentally" drain too much water if the power goes out. The best system I came up with [theoretically] would have a float valve to automatically re-fill the sump if after a power cut the level drops below the safe operating level for the pump, but what you've done there is fairly simple and should work well in your case.

[Shilo]

It was the safest thing I could think off. If the system is left too long in a power cut then the backup is the pumps run dry cut off but there will always somebody around the camp to turn the drain off within the 8'ish hour limit. 8hrs is a guess, although water will still be trickling in (25ltr/day) I won't be able to fine tune the tap enough to exactly match it, so with the sump full from a pump stoppage more will exit then enter even with the tap tuned in as close as I dare.

A float valve is okay but they do jam or leak (it happens too often here) so I don't trust them enough.

[#!CrunchBang]

What about using a float switch to turn the pump off when the water level is too low?

[Shilo]

Doable, but it still relies on a float and mechanical switch and in my case I want to try to keep things simple. My number one criteria in designing the tank system is of course fish health but number 2 is for it to be as maintenance free as possible (thus the automatic water change). Even if a float switch is only checked once every few months it still adds to the maintenance schedule.

Once the plumbing is done I will test things out to see how well it does work ( probably not at all! ),

[Shilo]

And it all fits together.

(Still have to put a grey trim down the side to cover the overflow.)

Edited September 6, 2015 by Shilo

[fish2water]

Wicked idea. Nice finishing. Good work.

[Shilo]

Thanks mate. Your foam will be going into that sump in the previous pic as an additional filtration to the wet/dry, reckon the combination should work very well.

[Shilo]

Warning: If you want some driftwood from the beach don't be too greedy and make sure the beach hasn't sanded in!

Last week I spotted a couple of good pieces close to the track but the beach had filled in since then so ended up walking a km to find the right piece, cut it off the log with a pruning sawn then lugged it back along the beach and over a huge sand dune to the car. Just about killed me! Once home I attacked it with a chainsaw and ended up removing half the wood so it would fit the tank - should have taken the saw to the beach with me and only carried half the weight.

Don't know what sort of wood it is but its solid and heavy so not pine or any other sappy wood. It should darken after being water blasted and soaked for a while.

Also made a cover for the overflow side of the tank. A simple bit of stained ply made a huge improvement on the overall look.

Plan is to fill under the wood with spray on foam to avoid any dead spots then cover the foam with grout / sand mix to blend in with the background I've yet to make (tomorrows job).

Edited September 6, 2015 by Shilo

[JaSa]

Great project - can't wait to see it finished :gpo2:

Cheers,

JaSa

[gligor]

What a fantastic job. Looks stunning so far. Inspires me to look at doing this myself some day

[reptilez]

Looks awesome! Coming together very nicely :thup:

[Shilo]

......can't wait to see it finished

I'm at that stage where I can't wait either! At a guess I think there is 2 months to go before its stocked, all depends on how fast the tank cycles once its up and running. Labour weekend is my deadline.

Just spent a small fortune on plumbing bits today :cry1: but managed to test out the chiller (it works!!!) and have sussed the plumbing design and where everything is going to go.

Also did the 3D background over the the last couple of days - didn't turn out anything like I wanted but reckon its good enough. Will post a pic once the grout's dried.

[maxxi1]

awesome build.

thanks for sharing

:gpo2: :cophot:

its going to look amazing

[Shilo]

Plumbing all fitted but not glued yet as I need a lot of clamps for the hoses and a couple of other fittings. Access under the overflow is VERY cramped but I can get my hand in there to adjust the taps as needed. Can't take a very good pic of it without removing some of the pipe work to move the tank away from the wall but:

To explain the system:

Overflow is a typical Herbie, 2 x 32mm bulkheads that join up to 40mm pvc (had to use 32mm because of room but already had 40mm pipe). The front bulkhead is the siphon and leads to a ball valve then piped through the wall into the wet/dry filter in the sump. 2nd bulkhead is the emergency / trickle one and is the same but without a valve.

A third 20mm bulkhead is down below at the bottom of the tank for water changes. From the bulkhead it T's off with one being the drain. This goes to a tap then through into the sump room, along the wall to the waste drain. The other also goes to a tap and through the wall but connects up with the charcoal filter and the mains.

This system should allow two types of water changes. For a 50 or so % change the drain tap is opened up fully and when the tank level reduces enough, its closed off then the other (fill) tap is turned on and water from the filter enters the same bulkhead and fills up the tank again. The other type is continuous. The fill tap is adjusted to let just a small trickle into the tank from the filter, this mixes with the tank water then the excess goes through the overflow system, into the sump, and out the sumps overflow into the waste drain.

I am hoping that bulk water changes will be unnecessary once the system is up and running but if it is needed it sure beats syphoning into buckets!

From the sump room pic below it looks like only one overflow pipe goes into the trickle filter because the main siphon one goes into the back of the top draw. The draw stand was a couple of cm too high to have the siphon pipe below horizontal if I put it through the top, should still work Ok and by doing this it has more drop.

Edited September 6, 2015 by Shilo

[Shilo]

Background was a fail, not happy with it at all - too many straight lines. Will dig out and replace the worse bits once I get some more grout.

Edited September 6, 2015 by Shilo

[kiwiraka]

Looking great I agree about the background, but much better than anything I could do good choice in wood though, I'm looking forward to seeing it full of fish

[gligor]

Maaaaate, that drip water change system is something to strive for. Awesome work!

[Shilo]

Filtration:

Overkill but better to have too much then not enough, its the same as in the DIY King video https://www.youtube.com/watch?v=YZJBm89MuzU but with a few minor changes. In the Wet/Dry the first draw has 3 layers of those green nylon pot scourers. I used them in my last tank and worked well for mechanical filtration and because they are cheap in bulk I figured why not again. Next draw is chock fill of bioballs which is above the sump water level and the bottom draw is full of sintered noodles and a few excess bioballs thrown in for good measure.

To prevent the top draw overflowing if the scouring pads block I drilled some holes in the top of the draw. Although excess water would come out over the top of the draws it would splash everywhere - with the holes it will just drain back into the sump. I also drilled large holes in the front of the lower draw to direct the water into the sump and around the frame so there is some water movement under there to prevent any areas stagnating or filling up with mulm.

Once the waters gone through the Wet/Dry there is additional filtration with some Poret foam. I just got a medium sump kit from fish2water and used the off cuts to separate the sponges. Because the Synfil doesn't self support I made a wooden frame (epoxy coated) and glued some gutter guard on it.

Haven't tested the system out yet but can't see why it wouldn't work. If the water pressure is too much for the foam (which I doubt) then I can simply make up some more brackets to support it.

Edited September 6, 2015 by Shilo

[Shilo]

Redone background:

Sorry about the reflections.

Also completed glueing and testing the plumbing and have put one of those cheap RBG LED light strips in the canopy. I don't want too much light because there will be no plants and the natives prefer filtered light so think it should work out well. Can always dim it with the remote if too strong or add another strip if not enough.

Edited September 6, 2015 by Shilo

[Tread50]

Looks Amazing :thup:

Definitely like the second effort with the background, the driftwood fits perfectly.

That filtration will only need to be cleaned out every couple of years :bggrn:

[Shilo]

Water:

Today's effort was to add some pool filter sand, scrounge up some rocks to throw in and WATER! Nerve wrecking experience since I hadn't tested out the tank full of water before now. It was made even worse with some of the regular campers grabbing a beer and standing around watching it in full anticipation of seeing the whole tank and especially the tanks maker explode and fall to pieces.

But it held and 6 hours later still no leaks with the filter system going full bore. :dnc1:

Now I need to get a test kit and start fishless cycling which is going to take awhile. So no pics for a while as there will be no changes.

Edited September 6, 2015 by Shilo

[kiwiraka]

!drool: Looks awesome and natural!

Incentive for me to do a rescape

[Shilo]

Before it looks really natural I need more rocks (will still leave some sand areas) and some algae/bio film growth on the background. I will keep the prominent bumps on the background clean but the hollows "dirty". Hoping it will look like a stream bank which is slowly eroding away a bank made up from deposited rocks from its old course.

Just a matter of time now.