DIY overflow box

[srfmon]

I'm running 2 Amiricle overflow boxes together. I mean they are right next to each other, so that there is no flow between the 2 of them (no flow at the wall where they meet).
I just wanted more flow. I'm running 2 mag7's on 2 sumps connected by a 2" BH. The only way the Amiracle could carry that much flow was to add a second overflow - so that's what ai did.
Now I'm thinking if I build a new skim box for the overflows that is one piece (instead of the 2 skim boxes I have now) would they more evenly distribute the water flow between each overflow box? Has anybody ever done something like this. I have the acrylic to do it. I'm just wondering if it's worth the effort. It seems like one of the overflow boxes is carrying one water back to the sump than the other. I was planning on adding an exteranl pump for even more flow. Maybe the mag7's can be teed together in one sump & the external pump on the other sump?

[Geoff]

here is the thread about the ones i made for my wife's 75g. you can make it wider for more surface area extraction if need be. you can also add wider PVC or drains and U-tubes. i think the basic dimensions i have listed will work up to 1.5" drains, maybe even larger. 1" are suppose to do about 500gph.

is there a reason why you are not making Closed Loops instead of trying to run so much flow through your sump? i think a CLS or two will be better for what you are asking than to make bigger overflows.

G~

[srfmon]

Oh no, a closed loop is also in the works as well. Maybe 2 of them (mag7 with a scwd & a mag18).
I'm just trying to simplify things - basically this already exists, so I thought by removing the wall between the 2 skimmer boxes (and making one big box) the water flow "load" to the sump would be more balanced.

[Geoff]

if the U-tubes are always maintaining siphon then connecting them would not make that much of a difference. connecting them would add an extra safety margin though. if a siphon were to stop or slow then you would still have the two drains at the other siphons disposal. i have found that difference is the two boxes could be as little as the tank not being dead on level and one box is lower than the other. or it could be that one slot was not made like the others and causing a little more or less flow into the pre-box. or it could be one of the siphons is a little clogged. to many variables to guess at. but connecting them together would give the illusion that they are working more evenly. the only way to tell for sure is to look at the ends of the actual drains.

G~

[wanareef]

Hay Geoff

I saw your diy overflows. On your gen 2's, the outside box if you made a piece of acrylic a little longer - like a "J" and take the short end of the "J" turned it upside down , that would hang the box but also leave you some room to drill two holes on the inside part and thd them for some screws.

On the inside "box" on the back side route two slots even with the two holes you drilled and threaded. You have an adjustable overflow- I had did mine like that and it has come in handy. I've had to readjust the "level" of the tank once or twice to bring it down.

On that "J" piece , I measured how much I wanted, cut it and used a heat gun to make the bend. Just wrapped it around a piece of 3/4" particle board. One piece no worries on the seams giving way.

On the drain out, I have seen several ways to maintain the siphon in the "U" tubes. What I did with mine is make a chamber, added a divider in the overflow so the drain is on one side and making sure the height of the divider is taller that the bottom of the "U" tube and the tubes on the other side.
The other way was to just have a big chamber but from the drain (BH) come up with a piece of pvc and also making sure it's higher than the bottom of the tube. Both work, both make a heck of a noise.

[Geoff]

thanks on the suggestions. i was planning something like that to make it adjustable. i like th "J" idea though.

i did put a dursa in each of the overflows so that they would be quiet. as for keeping the siphon going i put an airhose line in the top of the U-tube then ran this hose to the outlet of the return pump. this pulls any air that may have snuck in.

G~

[RWLydell]

I made three of these overflows to carry water from my refugium to my sump, which are both at the same level. Water flow is very slow, I just use 3 so I have 2 for backup in case of a clog.

Very simple and cheap. The 'buckets' are 2" PVC with end-caps and the 'U-tube' is 3/4" PVC with elbows. The 'buckets' are glued onto the U-tube with PVC solvent. The 'U-tube' extends down to within 1-2 inches of the bottom of the 'buckets'.

To prime it, I simply submerge the entire thing in the tank, then invert it to let the air trapped in the U-tube rise into the buckets, the turn it upright to let the air escape the buckets. I do this 2 or 3 times to get all the air out of the U-tube.

The level of each of the buckets is different, with the lower level being the drain side and the higher level being the intake side.

They aren't pretty but I've had them in service for about 3 months with no problems.

[Geoff]

i like it!

i like anything cheap and ugly. i need to do a nano that is totally DIY. as cheap and as ugly as i can make it. it it works, it is all good.

G~

[srfmon]

Okay, here's what I got. I went ahead with the plan because I figure if it didn't work I could scrap it. I did the teeth freehand with a router tonight. I know it's not perfect but it cost me nothing to make.
I chipped out some teeth but I figure it will still be okay. I'm going to wait to install it because I have some coral that has encrusted the overflows I have running at the moment. But as soon as they need fragging - I'm going to be testing this out.

[Geoff]

looks good!!! you might want to make the teeth longer. the way you have it now gives very little margin for error with water height in the tank.

i tried doing that with the router and boy did i make a melted mess. what speed did you use on the router and what kind of bit?

G~

[srfmon]

Here is the link to the router - router used
Anyway, I have it mounted to the underside of 1/2" acrylic. 24" x 24" clamped to my saw horses (yeah, I know, I'm getting a real table soon).
As for the bit used it was just a straight bit. There is no speed control on the router so I think it just runs at 20,000 rpm (scary when you think about it!).
Maybe I should get a bit that will make a square slot? I think that might be why I broke some teeth.

[srfmon]

Like I said I was going to do - I replaced 2 Amiricle HOB overflow boxes with a single box but this one has 2 U-tubes. The outer box has two 1" bulkheads as drains to the sumps.
Obviously it's a DIY job. So far so good, & it's been ten days since I put it in now.
The only thing that is bugging me now is the gurgling noise of water flushing down the PVC pipes on it's way to the sump.
Any ideas on cutting down the noise?

BTW - I have a clamp showing in the picture because I am looking for bigger nylon bolts & wing nuts. Does anyone know where I can get them?





Heres the pic with the clamp. Holding together the inner & outer boxes. It's actually safer than it was before because the previous boxes were cracked on the support & could have fallen to the floor at any time!

[snazlord]

Originally posted by Geoff
thanks on the suggestions. i was planning something like that to make it adjustable. i like th "J" idea though.

i did put a dursa in each of the overflows so that they would be quiet. as for keeping the siphon going i put an airhose line in the top of the U-tube then ran this hose to the outlet of the return pump. this pulls any air that may have snuck in.

G~

that's a great idea! can you elaborate on how you have the airhose connected on either end? did you just thread the airhose from the bottom of the U tube up to the top? Or did you drill a hole in the top of the U tube and silicone the airline to it? How does the airhose connect to the return pump outlet? Do you just have a T with a hose barb that the airline fits onto? It doesn't seem obvious to me that a T on the return pump line would cause suction to pull air/water out of the airhose (from the U tube) versus just pumping water out the airhose into the U tube.

Hope that makes sense.

[Geoff]

i actually drilled a hole in the top of the U-tube and inserted the airline tubing into the hole and sillyconed it in. this works for testing, sillycone and PVC do not stick. i have found another adhesive to try, but for now the hole is small enough that it is a good fit.

i then connected the other end of the airline hose to the venturi input on a small PH i had around. i just use the PH to circulate in the tank. just about any PH nowadays have a venturi valve on them. i just use this as an added safty measure to keep the siphons from loosing thier suck.

G~