Need more plumbing help :(

[mak3mydae]

DT water volume - 17g
Sump - 10g
Desired Flow - 100-200 gph

I'm having the most trouble deciding what kind of overflow i want. The more i read, the more i get lost...

In an earlier thread that i started, Uncleof6 said that the flow rate of the pump determines the flow needed for the overflow; the flowrate of the overflow must meet or exceed that of the pump.

He also said that the linear length or weir determines the flow of the overflow.

The calculator on the front page seems to not be working, so I have no idea how long the weir has to be for aprox 150gph. So if i just made the overflow box a little bit bigger to exceed the flow rate, wouldnt i be fine? So if i made a 3x6 with teeth =18 inches of straight line length then i should be fine, right?

Another big problem, is i have no idea what kind of overflow i want. I was thinking maybe just a herbie style, but undleof6 said that its not self adjusting or something, and althought i have no idea what that means, it doesnt sound too good :hammer: Also, with a herbie, you are controlling the amount of flow, so how would you determine the flow?

The other one that seems to be popular is a durso, but that an only handle 100gph? So i would need at least two?

If you were me, how would you plumb it?

Any help is greatly appreciated

[der_wille_zur_macht]

Don't get hung up on calculators and details. What you're looking for is a solution to a problem that can be solved many ways satisfactorily. 100 - 200 gph is a very small flow rate you're after.

You are correct - the maximum flow rate on the overflow must be higher than the flow you're pumping with the return pump. However, the flow rate through the overflow is much more closely linked to the standpipe design and diameter than the weir size - if your weir is too small, it won't stop working, the water flowing over it will just flow faster/thicker, which may lead to increased noise in some cases. Your overflow weir size will be more restricted by the smallest box you can still easily work with on a tank that small.

Regarding the drain pipe - a single 1" durso is simple to implement and will work totally fine at the flow rates you're after. Herbies, bean-styles, etc. are all great, especially on a larger tank, but on a tank that size, you'd take up half the volume creating a box large enough to contain the multiple standpipes you'd need for those designs.

So, plan on a 1" bulkhead, durso standpipe, and an overflow box big enough to contain it.

[mak3mydae]

Thanks a bunch.

Its my first time drilling a tank and I'm pretty scared that I'll mess up and end up with 20+(probaby nothing compared to bigger tanks) gallons on the floor. If 100gph isnt alot,what would be a pretty good amount of flow? 200?
TIA

[der_wille_zur_macht]

When I made that statement, I meant it in the sense of "100gph is easy to achieve." It should be more than enough sump flow for a 17g display.

[mak3mydae]

Ohhh, Thanks! So another question. How do i change the water level inside the sump? Say if the water level inside the sump was high enogh that if i were to turn of the pump, the water would overflow. with a sump more than half the size of my DT, i wouldnt have to worry about this, would i?

Since I'm on a 15 year old's budget, i plan to make my own overflow box. I heard that acrylic will not adhere to glass, so i planned to make a glass overflow. I also dont trust myself enough to cut teeth in the glass, so would i have any problems with an overflow box without teeth? How high should the overflow box be?

TIA

[der_wille_zur_macht]

A typical sump design will have one or more baffles separating it into different compartments. Typically, you set the height of the baffles to control the water level in the sump such that it is low enough to not overflow when the tank drains down. If you take this approach, the water level in the display and main sections of the sump will always be constant, but as evaporation occurs the water level in the return pump's compartment will drop.

You can use acrylic for the overflow. It is indeed hard to get a super strong bond between glass and acrylic, but it's easy to get a bond that's good enough for the purposes we need - many commercial and DIY'd glass tanks use acrylic overflows with high-grade silicone to glue it in place. The silicone won't stick super well to the acrylic, but it will certainly work in such a low-pressure application.

That said, glass is a fine choice, too. Don't get hung up on teeth - IMHO they just create extra noise and reduce the effective length of the overflow weir. If you're worried about stuff getting sucked or jumping into the overflow, cover it with eggcrate or mesh.

[mak3mydae]

How high should the baffles be in the sump? Should it only be high enough for the pump and skimmer to work?


You can spray paint glass thats going to be submersed with Krylon fusion right?

TIA

[der_wille_zur_macht]

Baffle height depends on many factors. You want it to be high enough for your equipment to work, and higher is better due to increased water volume, but low enough that it won't overflow when the system drains down. Another factor is the size of the return pump compartment - as evap occurs, water level there will drop. If your compartment is very small, it'll drop fast - which may cause issues if you don't have an ATO.

Krylon sticks well to plastic that is submerged. I've never used it on glass so I can't really answer that question.

[degener8]

The Krylon is a good choice for glass as well just make sure you prepare the surface correctly before painting so you get a good bond and make sure to allw it to cure fully before submerging.

[uncleof6]

The Krylon is a good choice for glass as well just make sure you prepare the surface correctly before painting so you get a good bond and make sure to allw it to cure fully before submerging.

I disagree, as Krylon is a paint for plastic, and there is no correct way to prep the glass. Putting it on glass, and submerging it, will give you a tank full of paint chips. Paint "systems" for glass that are reliable, cost hundreds of dollars per gallon, and as usual, things are not as simple as put forth. Paint your plastic pipe with it-- no problem, don't bother using it for glass.

Jim

[mak3mydae]

I've been reading more about spray painting overflowswith krylon, and it seems to be a pretty bad idea. I was thinking about getting some black glass from here
http://www.sundanceglass.com/fgbulstandard.htm
I emailed them and asked if it was safe to submerge.

Can you bond PVC to glass? AGE tanks have pvc bottoms.. so i assume its do-able. But i have no idea where to buy pvc sheets

[uncleof6]

It is not really doable at the hobby level.

Jim

[der_wille_zur_macht]

What's the application? Are you trying to put a PVC bottom on your tank, or just glue in an overflow? If just an overflow, use Acrylic, glass, or ABS and silicone it in with a fat bead of high quality silicone. It'll be fine. 90% of commercial and DIY tanks are assembled with ABS or acrylic overflows glued in this way.

If you're super picky about bond strength for your overflow, make it from plain clear glass, glue it in with silicone, then build a cover from thin black acrylic and glue that over the glass overflow. Then you get the color you want with the bond strength of glass-glass via silicone.

[mak3mydae]

Haha I am kinda worried... I dont want it to look like crap though. I've seen pictures of sumps with acrylic baffles and it looks like someone put the silicon on with a shovel just to get a good bond. I am fairly certain i am going to use glass for both my baffles and my overflow.

This may sound really stupid, but what if i used black silicone and smeared it really thin on the inside panel of glass on the overflow? Would this be disastrous?

Haha Sorry if i ask really stupid questions

[uncleof6]

Seam thickness between the edge of glass, and the face you wish to bond to should be around 1.5mm (1/16") thick, so smearing it will not really give you enough oomph if you know what I mean. Since silicone degrades over time when in contact with water, the seam needs to be protected with a sealing bead also. Using the right silicone, however, these seals can be rather small. Though you don't need the strength of Momentive RTV103, it is the best for all things aquarium related. Silicone does not bond with acrylic with any appreciable strength, and even by the shovel full, is not as strong as many believe. For a black overflow, you can get black glass, or smoked glass-- they cost a bit more, but you have the glass to glass advantage. Don't be tempted however, to use less than 6mm (1/4" nominal) glass.

The only stupid question is one that is not asked, unless you ask it more than once, expecting a different answer... ;)

Jim

[mak3mydae]

Who say's I'm not insane? :)

I had some more questions...

If the pump is too strong, i can always put a union valve on it to dial back some of the flow right? Would this harm to pump? Does it depend on what kind of pump?

How high should the overflow box be? My tank is 14 inches high, so would a 13 inch high overflow box be fine?

I plan to use a mag drive 1.9 since that'll put out about 130 gph at 4' of headhight. It says it'll accept a 3/8th inch flexible tubing. Does flex tubing fit right into a bulkhead? Or do i have to convert the flex tubing to PVC and then put that on the bulkhead?


I'm not sure if i can ask for stand help since this thread was labeled as plumbing help...

I'm finally back home, so i can get started on working on my tank :) Thanks to you two!

[der_wille_zur_macht]

Who say's I'm not insane? :)

I had some more questions...

If the pump is too strong, i can always put a union valve on it to dial back some of the flow right? Would this harm to pump? Does it depend on what kind of pump?

Yes, in general you can do this, and it won't harm the pump. Of course, the best policy is to pick the exact right pump for your configuration, but that's not always possible or practical.


How high should the overflow box be? My tank is 14 inches high, so would a 13 inch high overflow box be fine?

As high as you want the water level! 13" sounds OK.

I plan to use a mag drive 1.9 since that'll put out about 130 gph at 4' of headhight. It says it'll accept a 3/8th inch flexible tubing. Does flex tubing fit right into a bulkhead? Or do i have to convert the flex tubing to PVC and then put that on the bulkhead?

The tubing should mate directly to the pump if it's advertised to fit that size. At the other end, you have two choices - you can use a bulkhead to go through the glass, or you can go "over the back." If you use a bulkhead, you'll have to use a hose nipple to "switch" from the hose to the bulkhead. If you go over the back, you have a few options - PVC elbows, loc-line, etc.

[sjm817]

For a small setup like that, just keep it simple. You could use an upturned 90 fitting for the overflow. Maybe a 2" to 1" street elbow or similar. You would use 1" bulkhead and a Durso style T on the outside. For a pump, a Maxijet 1200 would work, or an Eheim 1250 if you want a little more powerful and a nicer pump. For height, it depends. If the tank has trim or a canopy, just high enough so you dont see the water level. You can put the top of the overflow just a hair below the edge of the trim.

Another option would be to get the nano overflow kit from glass-holes.com. It is a complete kit with instructions to do the whole project. Even comes with the glass hole saw.

http://glass-holes.com/Super-Nano-Overflow-Kit-ghsnanokit.htm

[mak3mydae]

der_wille_zur_macht - I'll probably use a hose nipple. I need a plastic hose clamp to secure it, right?

sjm817- I thought that something like that wouldnt be able to skim the surface very well without being loud? And to be honest, it just... kinda looks funny haha. I was thinking about getting the ehiem, but it seems to have a little bit too much flow. I was under the impression that a durso can only handle about 150gph? My tank is a rimless tank, so there really no hiding the water level haha, but i figured i'd make it a little bit lower just so water doesnt splash ever for whatever reason. I also plan on doing some DIY LED's so i need some surface disturbance for glitter/shimmer lines.
I was also thinking about getting one of those kits, but i'm not sure how loud they are. No one really seems to talk about that... they just say that glass-hole's customer service is amazing. And i dont have enough faith in myself to drill my tank. Maybe my sump, but not my DT. I know 160 probably isnt that much compared to larger tanks, but this is all on a 16 year old's budget :)

[sjm817]

I agree on the aesthetics of the upturned 90. It would work, have enough surface skimming for a 17G, but not be great looking. Just throwing it out there. A Durso can handle more than 150 GPH. For one, they are not all the same. There are different sizes and designs, It would not be a problem with your setup or much much larger.

If you dont want to drill the tank none of what has been discussed matters. All of what has been discussed requires drilling. If you dont want to drill, you are looking at a HOB siphon setup which is difficult on a low flow small system. It will be noisier and will likely require a higher GPH. Lifereef makes a nano HOB overflow that would probably work well.
http://www.lifereef.com/siphon.html

[mak3mydae]

Forgot to mention, I wont be drilling it. I'm getting my LFS to drill it. Have you used the glass-holes overflow box? Is it quiet?

[sjm817]

I haven't used that one personally, but have used similar setups. With the low flow setup you will be running, it will be quiet. You can get the G-H kit, and bring it and the tank to the LFS and have them drill it.

[mak3mydae]

The more i look into it, getting the GH kit does seem easier haha. Where do people put their return lines? Are these likely to get clogged up?

Random question, what are the odds of someone over-tightening a bulkhead?

[sjm817]

The return can just go over the top edge. No, they dont clog. Bulkheads get tightened just a bit more than hand tight. A decent LFS should know what they are doing.

[mak3mydae]

Ok... um... as for a return, I plan on getting my LFS to drill that as well. I've decided i dont want to hang it, so I'm going to put it under the overflow. With this, is it possible that when the power goes out, it'll start a siphon and drain water until the return line? Is there some kind of check valve i can put on the return line?

The pump takes 1/2 inch fitting, so i need 1/2 inch flexible PVC. This goes into one of these

http://www.marinedepot.com/Insert_Elbow_Fitting_1_2_inch_FPT_x_1_2_inch_Insert_Hose_Barb_Fittings-Spears-FT7133-FIFTFIHB-FT7133-vi.html

and that fitting can connect to
€
http://www.marinedepot.com/ps_ViewItem.aspx?category=Standard_Threaded_Bulkhead_(Schedule_80_Heavy_Duty)_1_2_inch_Slip_x_1_2_in ch_FPT_Standard_Bulkheads&vendor=Spears&idProduct=FT1121&IdCategory=FIFTBHSB&child=FT1121&tab=4&size=1/2%20Inch

right?

From there, i use this?

http://www.marinedepot.com/Loc_Line_1_2_inch_Ball_Socket_x_MPT_Connector_1_2_Inch_Loc_Line_Plumbing_Parts-Loc_Line-LL1119-FIFTLLHI-vi.html

Sorry for all the links. Haha this thread probably doesnt deserve to be in this forum

[sjm817]

I can understand aesthetically not wanting to go over the top on a rimless tank. There is a problem putting it under the overflow. With it that low in the tank, it will back siphon a lot of water and overflow the sump when power is off. You want the output of the return just below the surface. What you can do is put another bulkhead in that would put the return outlet in an inconspicuous spot like near a corner. I would use a standard schedule 40 bulkhead instead since they are smaller. I would also use 3/4" for the return plumbing. 1/2" is very flow restricting even for low flow apps. Yes, from there you can use a loc line fitting of your choice.

[mak3mydae]

Would 3/4" be too big if the pump asks for 1/2?

So instead of the 1/2 inch bulkhead, i would get this 3/4 inch one? Is this one schedule 40?
http://www.marinedepot.com/Double_Threaded_Bulkhead_Fitting_3_4_inch_Double_Threaded_Bulkheads-Spears-FT1131-FIFTBHDT-FT1133-vi.html

I'm not sure what it means by double threaded. Can i use this?
http://www.marinedepot.com/Insert_Fitting_3_4_inch_MPT_x_3_4_inch_Insert_Hose_Barb_Fittings-Spears-FT7333-FIFTFIHB-FT7344-vi.html

[sjm817]

You can upsize the plumbing. Double threaded means it has threads on both sides of the bulkhead. Sometimes slip fittings are used which must be glued. Double thread would work well for your application. I would think you would want a fitting more like this one so it can point down.

http://www.marinedepot.com/Insert_Elbow_Fitting_MPT_x_Insert_Hose_Barb_Fittings-Spears-FT7533-FIFTFIHB-vi.html

You also have to find something to adapt the 1/2" outlet of the pump to 3/4" barb.

[mak3mydae]

You also have to find something to adapt the 1/2" outlet of the pump to 3/4" barb.

That lost me :(

So am i still using a 1/2 inch flexible pvc?

[sjm817]

Larger plumbing allows more flow. 3/4" is much less restrictive than 1/2". Assuming you are using a Maxijet 1200 (are you?) for the return, you would adapt the 1/2" of the MJ to 3/4" and run 3/4" tubing to the 3/4" bulkhead. Flex PVC is not what you use with hose barbs. Flex PVC is glued like standard PVC. With barbs, your would use vinyl tubing.

With that said, using 1/2" may work. What I'm not sure of is if the 1/2" will cut the flow back too much and not get you enough. It may be fine but is hard to say for sure. The 3/4" would give you some margin for error.

[mak3mydae]

No, I ended up choosing the eheim 1250 and it also has a 1/2 inch outlet. If i do use vinyl tubing, how do i use the 3/4 inch tubing? Will it still fit on the outlet? What do i use to adapt the 1/2 to 3/4?

[sjm817]

The Eheim 1250 has more power than the MJ so I would just do everything including the bulkhead 1/2" to make it easy :)

[mak3mydae]

LOL I am extremely slow when it comes to stuff like this... Thank you for all the help though :)

[sjm817]

You are fine. Great to see that you are taking your time to research and do it right and to ask for advice. :thumbsup:

[der_wille_zur_macht]

You do NOT want the return bulkhead that low in the tank. Check valves are not reliable enough to prevent siphoning the tank down to that point. Put it up high, next to the overflow box or through a different wall in the tank. And use a siphon break hole, too.

Regarding your links - close, but not quite right. The first link is a 90 degree nipple to female pipe thread. If you'll be using a threaded bulkhead, you want MALE pipe thread on the fittings, as the bulkhead will be female threaded. The male threads on the outside of the bulkhead are ONLY for the bulkhead nut, not for pipe threaded fittings.

You got the link for a bulkhead that's threaded on one side and slip on the other. If you want to use all threaded fittings, you need one that's threaded on both sides.

The loc-line you linked to looks good though, but keep in mind that's just the threaded adapter. You'll want at least a few links and maybe a nozzle.

[sjm817]

Since you are getting the G-H overflow kit, you could also get the 1/2" return kit while you are at it and take the guesswork out of it.

http://glass-holes.com/1-2-Inch-Return-Kit-return50.htm

[mak3mydae]

I ordered my stuff from Gl*******s. I got the overflow, one adapter, a 5inch piece, and a flare nozzle.

From Marine Depot, I decided to just get a skimmer, the pump, and a few plastic hose clamps. My LFS has a pretty wide variety of plumbing parts, so i took down a list of all the things that you guys wrote and i plan on going there today.

Thanks for all the help you guys :)

[sjm817]

Looks good. I would be sure to be very clear when telling the LFS where you want the holes for the overflow and return drilled. I would actually use a marker and draw the circles.