Hi,

Im just trying to design a closed loop for my tank. using Pies idea of actually "drilling" and plumbing up holes in the tank at the back/bottom or underneath, my concern if a pipe accidentally popped off the loop somewhere, it would drain the entire tank. So, thinking of how typical sink pipes work, i thought about designing the loop as follows (specifically the yellow pipe design)

Side on shot of the tank:

The worst that could happen here if a pipe popped off the pump (or anywhere except the connection attached to the tank itself) the tank could only drain down to the water line shown by the red line above. This design could work with those without "in-wall" tanks, as long as you had a hood you would see the pipe sticking above the water level.

Can anyone see any issues with this design or offer any advice? Cheers.

If the break is below tank level the yellow pipe will sypon until it gets air in it.

I belive its un-nessessary to build this in, pipes don't leak or 'pop off'.

However, your diagram would prevent this from happening.

A big advantage of using the closed loop is the ability of hiding ALL internal plumbing, using your system as pictured would mean that the inlets would be visible from the viewing area of the tank. Not ideal.

IF your worried about pipes popping off, what if the yellow pipe pops off... I think all the extra piping you are considering will introduce more problems than it will solve.

Here is some pics incl a diag of my closed loop locations (top down).

Not for you pieman as yr tank will be 2 big! but for Chimera.... just use 2 streams and you won't need all that pipework which if you added it up the streams might be an option! thoughts please.

I am going to use Streams too! I belive, that to get good flow through the rockwork, and create more current options you can't go pass the closed loops. Streams for the corals on top.

The advantage of the closed loops is you don't see them, and they are almost perfectly silent.

Use both...

reread my post. chimera could just about get away with streams only, as he's doing the less rock more freespace effect.

Streams are great, but when i get around to setting up a bigger tank, i think i'll go with a "swiss cheese" backwall full of closed loops (plus some through rock structures), much less intrusive than powerheads/streams.

Layton

Steve is close on what i want to achieve - similar to the tank he setup in Takapuna. There will be a large rock face up on the left (say about 400mm), almost to the bottom of the overflow. then looking right, there will be a small (say 50cm gap) with no (or minimum) rocks at all. then, the rest of the tank (to the right) will be a reef of low/mid/high-height rocks. the right side will sit on a reef rack with closed loops underneath. each closed loop (want 3 for a 5 foot tank) will have water flow similar to what SCWD's achieve - ie: out one side for 20 seconds then out the other side. however, one side will flow the bottom of the tank then the other side will flow the top of the tank. that way current alternates high and low randomly between all 3 closed loops. i will be allowing (not sure how?) for streams in the future (will allow for at least 2)

any comments welcome, thanks.

Either way will work fine. my point was cost effectiveness plumbing aint cheap when u add up all the bits plus then pumps & drilling holes etc, bet the streams start to look more attractive

there is going to be one hell of alot of plumbing anyway so a few more bits and pieces here and there aint gonna make much difference

Use both, closep loops work out to be about a bit more expensive per each as a single 6100 stream. (pump, 2x taps, plumbing fittings, timer?, internal spray bar, strainer). Based on using an Ehiem 1262 for the closed loop.

Closed loops through the rock work, streams to fire the current accross the corals. I use 2 streams in my 5ft and its fine, but I also have 2 closed loops and 1 sump return. My tank had good strong water flow. Your 5 footer will be smaller than mine by over 150 litres (mine is 740) so similar setup should workout fine.

Pies

cheers pieman, good plan. closed loops for bottom (water flow across substrate) and streams for the top (corals)

Pies, with all those holes at the bottom of the tank is surly very risky. If one hole cracks then it will split the bottom glass.

Also all that piping and pump. If it leaks it could drain the whole tank.

Simply is best and safer.

I think placing one stream at the bottom next to the overflow should be enough to circulate the bottom

kind of what i was thinking for chimera, maybe just one closed loop with a full lengh spraybar?

perhaps, but the 2nd closed loop will be used as a "stream" until i can afford real ones!!!

perhaps, but the 2nd closed loop will be used as a "stream" until i can afford real ones

do in once and do it right the first time, will cost less in the long run. plumbing is bloody expensive.

hmmm, true. dammit this hobby requires a pay rise!!!

Pies, with all those holes at the bottom of the tank is surly very risky. If one hole cracks then it will split the bottom glass.

Interesting, as most of us here (including you) already have holes drilled into the bottom of our tanks. How many is too many? 2 or less is not risky, but 2 or more is risky? How about 3, is that OK? To me makes no difference. 1 or 10. Once they are in they are in. The bottom of my tank will be 22mm thick (2 ply) so cracks are not really a major concern (check Annas tank construction pics on UR). As long as the bottom of the tank is level and supported it will not be a problem, 1 hole or 100 holes. The only reason I am not putting more in is the cost of the plumbing.

If just streams was the best option, then I would use them, would be cheaper in my case, however I will get much better results using closed loop pumps. If you put pumps under the rockwork you can't remove them for maintenance without huge amounts of rockwork disruption. Got pumps in the tank, got to get the power cords out too. Streams are good, but provide no circulation throught the rockwork. Spray bars are the way to go, but on a large tank you need more than one, in my case I ave opted for 4.

Chimera - use both, a closed loop is not a cheap substitute for a stream, its has a different application. If you are uncofortable with having holes drilled into the tank, then don't do it. Go through the hastle of sumerging a pump into the tank or just don't bother.

Why is plumbing so expensive anyway? I suspect my tank will cost over $750 to plumb, thats a lot of money for 'nothing'.

Having quite a bit of experience in the glass industry, I sleep well at night knowing I have no holes at the bottom of my tank.

Putting two pieces of glass together is even worse. Glass against Glass is very dangerous, unless you are going to put silicon in between, however the cost of the silicon is high.

15mm glass will be ok, costs more but much safer.

Plumbing could be a problem? The threads on the plumbing might not fit through the thickness of the glass.

Really?

Alois - You do have holes in the back glass though, which is more dangerous than the bottom. I was originally going to drill through the sides, but was warned off it.

Silicone is cheap as chips and both pieces will be siliconed together. The plumbing can be used to attach through 40mm wall so won't be a problem.

My current tank has about 5 holes in it, and my grow-out tank has 3 holes, no of which have given me any problems.

Sure there is some risk, but I think the benifit outweighs it

i fail to see how two holes on the side is more risky that the bottom?

The biggest and best reef is in my house and still going after two years with two holes on the side .

The biggest and best reef is in my house and still going after two years with two holes on the side.

Hahahahahaha

modest that fishgod