Rcpilot - 29g Frag Tank

Rcpilot

Reef enthusiast
Thought I'd go ahead and start this thread. This will be a slow moving thread in the beginning, since I don't have the bulkheads
and a few pieces of lumber that I need. It's in the planning stages right now. Hopefully this will pick up speed and finish out
nicely.

As many of you know, I currently have a 10g frag tank.

IMG_2243.jpg


It works good, but I never did set it up right and it's more of a nano with frags than a true frag tank. I think Biff coined the phrase
"Fragano" :mrgreen: The tank has about 10-12lbs of live rock and a sand bed. I've just purchased magnetic frag racks from
here: Blackrock Reef
As you can see from the picture above, it's possible to fit 4 of these racks in the tank and load them up with about 80 frag plugs.
I've been using frag plugs from Currently Undergoing Maintenance and really like the products. But the tank gets pretty crowded
and hard to maintain because upper racks have to be moved in order to access frags on the lower racks. It works, but it's
crowded.

I've been running the tank without any fish for a few months, but recently rescued a 3-stripe damsel from a local fish keeper. The
fish had matured and become aggressive in his 55g tank. Typical damsel. The guy was going to flush the fish if nobody came
over to get it within a few days. I had been wanting a fish and didn't really care what kind of fish it was, so off I went, to rescue this
poor juvenile delinquent. The fish is like a crazed squirrel in this little 10g tank. It displays neurotic behavior that I can only
attribute to the shock of being moved to a VERY bright 10g tank. Consider this little fish came from a dimly lit 55g tank and it
makes it easier to understand why it's acting pretty freaked out with it's new surroundings.

Sooooo, not only did I rescue this fish from a trip down the American Standard whirlpool of freshwater death ........ I'm taking my
perfectly functional 10g frag tank apart and transferring all the contents to a 29g tank ........ just for the benefit of the fish. Just so it
can "stretch it's legs" if you will.

I know. I'm a total softy. :sfish:

Here's the plan:
I have a dry 29g tank. It measures 30L x 12W x 19H This will be the frag tank.

I also have a 5.5g tank that measures 16L x 8W x 10H This will be the sump.

I'm going to build a wood stand that measures approx 48L x 24W. I'll set the 2 tanks on top of the stand with the 5.5g on the left
side of the frag tank. The 5.5g tank is going to sit on a wood shelf or step that will put the top of the 2 tanks even with each other.

There is going to be a 1.5" overflow line drilled in the back of the 29g tank and piped over to the back of the 5.5g tank. This is a simple
matter of drilling (2) 2 3/8" holes and installing the 1 1/2" bulkheads. Then run a couple pieces of pipe and valves to connect the 2
tanks. I'll construct an overflow box from lexan polycarbonate
(thanks to Pat @ Stonehouse Signs in Arvada, CO. for the free lexan. :Cheers:).
The overflow box will be located inside the 29g tank - in front of the bulkhead. As with any other tank, the teeth in the overflow box
control the height of the water in the tank.

I'll be using a HOB refugium for filtration. It's the small refugium available from here:
http://shop.aquatraders.com/Hang-On-Refugium-with-Protein-Skimmer-14in-p/43016.htm
I am already using this refugium on the 10g tank. It will simply be swapped over to the new frag system. I'm not going to drain
it or replace the sand. I'm just going to unplug it, pull it off the back of the existing 10g frag tank, run across the room and slap it on
the back of my new frag system. My rationalization here is that this is a functioning refugium with an established DSB, live rock
rubble and cheato. It's loaded with pods of all manner. No sense in starting fresh if I have a good refugium sitting here.

Here are some crude drawings that I created in Microsoft Paint.

This is the top view:
29gHOBPipe.jpg


And the same top view with measurements:
29gFrag.jpg


This is a side view looking from the front:
29gFraga.jpg


The HOB refugium is going to hang on both tanks. The MJ1200 powerhead will be located in the 5.5g sump. The outlet for the refugium
will dump into the 29g tank. The 29g tank will fill and dump into the overflow and bulkhead. Then water will run via a 1 1/2" PVC pipe
back over to the 5.5g tank.

Why am I doing it like this?

Because I need to utilize the equipment I have on hand. There is not much money in the budget and this tank needs to be put together
as cheap as humanly possible. My budget is NOT TO EXCEED $50.

By placing the MJ1200 powerhead (powers the refugium) in the 5.5g tank, this becomes the sump. The water level in the 29g tank will
always remain constant because the tank must fill up to the top of the overflow box before it can escape though the bulkhead.
Water level in the refugium will remain constant. The design of a HOB refugium makes it fill with the powerhead up and above the
level of water in the tank. It overflows a final baffle on the right side and then goes back into the tank. The only place the water level
will fluctuate is in the 5.5g sump. Since this is where the powerhead pulls water from, and everything else is baffled - the only place
the water levels will fluctuate is in the 5.5g tank. I am doing it this way, so that I don't have to worry about changing water levels in
the tank. Simply perform daily top offs into the 5.5g sump.

Hope that makes sense.

I plan to utilize the 78w PC light that I currently have on the 10g frag. I just need to install a cross brace about 20" from the end of
the 29g tank. The 29g tank doesn't have a factory support in the center, and my light legs run horizontally, so I need a
cross support 20" from the right side of the tank.

With the refugium on the left side, and the overflow in the dead center of the back, I have quite a bit of room to place my magnetic frag
racks on 3 sides of the tank. I will be able to put racks on the back, right side and front. In the future, I should be able to load up the
entire right side of this tank with frag racks.

I'll purchase a T5 light down the road. For now, the frag racks will simply be placed closer to the top of the tank. The 78w PC light is
more than enough to grow frags that are placed within 4 - 6 inches of the surface.

And the biggest benefit of all - the little damsel gets a whole 29g tank to swim around in. Thats the whole idea behind this
adventure. Settle in for a ride my friends. This is gonna be fun. None of it is going to be pretty. But it's gonna be fun!!
 
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Been thinking about the filtration on the tank. Decided I might put a DSB in the tank, but only on one end. I got free lexan here and it
cuts pretty easy with a band saw. I can cut a 12 x 8 baffle and place it cross ways on the left side. If I place this baffle about 12" from
the left side, I can get a 12 x 6 DSB on the left side about 6 -7" deep. I'll cut a few triangles to brace the bulkhead and keep it from bowing or blowing out.

Side view:

29gFragb.jpg


Top view:
29gc.jpg



It's probably not necessary, but y'all know how much I love a nitrate free tank. It'll boost the HOB filter and help grow pods. I just
don't want a full sand bed in the tank. I don't want the maintenance. I think a "contained" DSB on one end of the tank will do the
job I'm after and hopefully if I don't fill it the entire 8" depth and leave a 1" of 2" lip on the edge it will keep the sand contained
somewhat.
 
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umm I am a little confused. How are you getting water back to the 5.5 sump? I think I read a overflow bulkhead will bring the water back over. However the top of both tanks is going to be the same height. So it overflows into the the line then runs over to the sump. Wont that line have to be a angle at least to have flow? Then when it gets to the sump how does it get into the tank? If the line from the 29 is at a angle it will end up at the bottom or near bottom of the sump. I know I am probably missing something here and you know more about sumps and such then I do however I dont see how the water gets into the sump with this configuration.
 
ok I re-read your post again. I think what you are saying is both tanks will be connected via the piping. Ok so the tanks are going to be hard connected. The 29 will have a overflow box in front of that bulkhead. That will keep the 29 at a constant level. I understand that so far. Will you be able to get enough pressure to keep flow going from the 29 to the 5.5? I guess that would be the real question. Will the line be bringing in the water to the 5.5 at its water level? Or will in be underwater? I guess it all depends on where the water level of the sump is. The hang on back fuge has its pump about four inches below the top of the tank (at least mine is and we have the same fuge) so if the line going from the 29 is at that level then i guess that might work. However if the water goes down even a little then the pump on the fuge will be sucking air. Please enlighten me. This is a great idea and gives me something I might like to try on my own tank.
 
ok I re-read your post again. I think what you are saying is both tanks will be connected via the piping. Ok so the tanks are going to be hard connected.

Correct.

The 29 will have a overflow box in front of that bulkhead. That will keep the 29 at a constant level. I understand that so far.
Stay with me.

Will you be able to get enough pressure to keep flow going from the 29 to the 5.5? I guess that would be the real question.
It HAS too. If the 29g tank fills up and spills over the overflow and into the piping, it HAS to move the water over to the 5.5g tank. It can't go anywhere else.

Will the line be bringing in the water to the 5.5 at its water level? Or will in be underwater? I guess it all depends on where the water level of the sump is.
Yes, it depends on how fast the MJ1200 sucks the water out of the 5.5g sump. The MJ1200 is rated at 300GPH with no head pressure, so let's call it 250GPH since it has to pump the water uphill to get it into the refugium. And let's just say it's a 5g tank. Makes the math easier.

250GPH pump pulling out of a 5g sump. That means it can empty the sump 50 times per hour. Thats about 4g per minute.

As long as the pump runs, it'll push 250GPH +/- through the refugium and into the 29g tank. As long as the 29g tank continues to overflow - the water will have no choice but to go back to the 5.5g sump. It has too.

Think of it this way - the 5.5g sump is under a vacuum because there is a pump in there trying to suck it dry. The 29g tank is under pressure because it's being filled to the point of overflowing.. Flow will always go from the higher pressure to the lower pressure.

The hang on back fuge has its pump about four inches below the top of the tank (at least mine is and we have the same fuge) so if the line going from the 29 is at that level then i guess that might work. However if the water goes down even a little then the pump on the fuge will be sucking air. Please enlighten me. This is a great idea and gives me something I might like to try on my own tank.
Doesn't matter where the pump is. Think of it this way:
In a "typical" setup, your sump would be underneath the main tank. Doesn't matter WHERE the bulkhead for the overflow is located. When the tank fills up, it overflows. Period. The overflow water MUST go somewhere. The pipe simply directs the water back to the sump.

Doesn't matter if the pump is in the bottom of a 15 foot deep sump. Doesn't matter if it's 4" below the surface. The sump will continue to fill just as fast as it's being pumped out. It HAS TO. There's no place else for the water to go once it reaches the overflow.


Here is a typical sump setup. Tank on top. Sump on bottom. What keeps the pump from sucking air and running dry? You simply have to put enough water in the system. Once the main tank upstairs fills up and begins to overflow -- it's continuous. The main tank is only going to overflow as fast as the pump can push the water back into the tank.

The pump isn't going to run dry, because you've filled your sump to an appropriate level and it's constantly being filled via the overflow.
29gSump.jpg


Okay, now let's play hypothetical and slap the refugium in. So? The water simply passes through it. It doesn't back up because it has an overflow. It's going to fill until it hits that last baffle and then it's going to overflow. Doesn't matter WHERE it overflows too. It can overflow right back into the 5.5g tank, or it can overflow into the 29g tank. Whats the difference? And it won't flow out any faster than the pump can push the water in.
29gSumpa.jpg


The water simply travels from the 5.5g sump -- up and into the refugium. The height of the refugium makes no difference here. The height of the pump also makes no difference. As long as you have a strong enough pump to push the water that 4 or 5 inches up into the refugium - it works.

Now the refugium overflows. So it overflows into a completely full 29g tank that is already overflowing out the box box.

The water has now moved from the sump - through the refugium (nothing more than an oversized giant pipe that happens to have some sand in it.) - and down into the 29g tank -- over the teeth on the overflow -- through the bulkhead - down the pipe - and back into the 5.5g sump.

The sump can't get sucked dry because the 29g tank is constantly overflowing back into it.

I hope that makes sense. I hope it works too!! :mrgreen:
 
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I'm starting to wonder now. Ted's got my brain smoking' . :shock:

Yes, a 1.5" PVC pipe is rated for about 900GPH. But thats DOWNHILL. I was planning to run my pipe from the 29g over to the 5.5g sump HORIZONTALLY or maybe with only 1/2" drop on the 30" +/- it will run across from the center of the 29g -- behind the refugium -- and into the left side of the 5.5g tank.

Will it flow the 250-300GPH I'll be getting out of the MJ1200 thats pushing all this water? Sure, it'll flow 3x that much going downhill. Will it do it horizontally?

If the hole for a 1.5" bulkhead is actually 2 3/8 inches -- I think it would be prudent to make the TOP of the bulkhead hole at least that same distance (2 3/8 inches) from the top edge of the tank. You don;t want to go drilling a hole 3/4" from the top edge of the tank, you might break it - or at least the risk of breakage is higher. But I'm not sure just how close to the top edge I can drill that hole. Never done this before..

IF the edge of the hole is 2 3/8 from the top of the glass in the 29g tank, then the centerline of the hole is going to be at 3 9/16 inches from the top edge.

The 5.5g tank is 10 inches deep. That puts the bottom of the bulkhead hole at (let's see 2 3/8 + 2 3/8 carry the 2 and dot the lowercase J) -- 4 3/4 inches from the top. Tank is 10 inches tall, so minus the 4 and 3/4 (carry the not - cross the Tee - subtract the double not) - that puts the bottom of the hole at5 1/4 inches up from the bottom of the tank. Center of the 1.5 inch inlet pipe will be at 3 9/16 down from the top and 6 7/16 up from the bottom.

I think.

That means my sump is only going to be about 6 inches deep when it's full of water. Unless I pour in enough water so the inlet tube is 1/2 way under water. Another 3/4 inch of water.

Thats a 3.3g sump.

And thats is the PVC pipe is LEVEL.

We need a bigger boat!! Might have to use the 10g tank instead. :12: My head hurts.
 
See there Rc.It aint no different than pushing air through a duct system,except the effects of gravity:D
 
Is it that easy Yote? I've never done a sump and this is getting complicated. I don't want to reinvent the wheel. I make things too complicated sometimes. Actually I do it a lot. I over-engineer things and they end up complicated and unproven designs. Sometimes it works. A LOT of the time it works. But I can't afford to fail on this. I need it to WORK.

My wife just talked me into a 10-15g sump UNDER the stand - like any normal tank. I just need a water pump to move water back up to the 29g tank. A 700 -- 1000GPH pump should do the trick if you consider about 4 feet of total head and loss from friction or bends in the plumbing.

I might do this if I can source a craigsist a pump on the cheap. Can probably get another 10g tank or maybe even a 15g tank on craigslist too.

This makes my stand construction WAY easier. It takes one bulkhead out of the equation, so that saves me money on the plumbing parts and complexity. It takes a LOT of wood and fabrication time out of the stand. It makes the whole project more compact. Thats a good thing considering I'm in an apartment with very limited space already. Instead of a 48" x 24" stand with 2 different shelves on top, I go to a 36" x 24" stand. Your basic table with 4 legs and a solid top deck. That still gives me plenty of room to stuff a 10g or 15g sump under it the stand WITH the existing Aqua Traders refugium hanging on the back that sump.

I'll need 2 baffles in this sump. Where the 1.5" inlet pipe dumps into the sump, I'll need a bubble trap to keep them out of the return area. Thats kinda why I need a dry tank. Need to put some baffles in it before it can co under the stand and get wet - or I'd just use my existing 10g tank and save the money.
 
One thing I've noticed,is 99.9% of the time,people do over complicate a sump.
All you really need is an over flow box,some glass or plexi-glass for the baffles,and a return pump.
Gravity feed water to the skimmer section of the sump.through a set of double baffles,then into the return section.Thats all there is to it.
For the refugium,if your gonna use you HOB,just feed it from the sump and let it run back into the sump.
And do go with a high GPH return pump.You actually just want a gentle flow through your sump.That way the fuge and skimmer have plenty of time to do their jobs.I'd actually suggest something along the lines of a Mag 5,maybe even go with something a little smaller.
 
One thing I've noticed,is 99.9% of the time,people do over complicate a sump.
All you really need is an over flow box,some glass or plexi-glass for the baffles,and a return pump.
Gravity feed water to the skimmer section of the sump.through a set of double baffles,then into the return section.Thats all there is to it.
For the refugium,if your gonna use you HOB,just feed it from the sump and let it run back into the sump.
And do go with a high GPH return pump.You actually just want a gentle flow through your sump.That way the fuge and skimmer have plenty of time to do their jobs.I'd actually suggest something along the lines of a Mag 5,maybe even go with something a little smaller.

Thats exactly it Yote. There's free 10-30g tanks on craigslist right now. I just looked. Not sure what size sump to get. I think 10g would be the minimum. 20H sounds nice, until you figure out how tall that makes the whole setup. I don't want to be on a step ladder to get my hand in the tank - and my hand is gonna be in there a lot. It's a frag tank. Could try for a 20L or a 15L

I was just gonna leave the HOB refugium right there on the sump and let it circulate in there. It gets all the water eventually. It all has to flow through there at some point.
 
Ya I think doing the standard underneath sump probable will work better. The other idea had some very interesting ideas though. I will have to file that one in my brain somewhere. I eventually want to put two 125 tanks on either end of my corner tank and link them all together. My original idea was just have the sump running on all three tanks. But if I could link them with bulkheads that could be interesting also.
 
Yote,
I got a 29g here that I was gonna use for the frag tank. I think a 20L would be best under the stand. It gives me room to put in a baffle to stop air bubbles from where the overflow pipe comes down and dumps into the sump. Gives me room to use the HOB refugium. And still leaves probably 10-12g for the sump with room over fill in the event of power outage.

What do ya want for a sump? Long or tall? I see 3 different sizes for the 20g tanks:

Tall = 24Lx12Wx18H
Long = 30Lx13Wx13H
Long = 24Lx13Wx21H (that seams like a REALLY tall version instead of a long)
 
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