Advice to setting up return lines to the display tank

[Capslock]

Hello,

I have a couple of ideas on how I would like to setup my return lines to the display tank and I am looking for some suggestions. I decided to write them down so you had, well, at least something to look at.

Both return lines in both images would be connected via a Y split from a single pump

The top left most sketch, on line points to the overflow while the other line, next to the overflow points toward the front of the tank

The top right most sketch, only one return line facing toward the front of the tank

the bottom center sketch, both lines are next to each other (the one in the left would probably be in the middle of the tank); the line on the left pointing away from the overflow while the return on the right points toward the front of the tank.

My intentions are to achieve a circular flow through the display tank.
Good idea? Bad Idea? What can I improve on here?

Side question: when connecting pvc together, how do I make the pipes water tight?

 

[Capslock]

Oh, I guess I should say more information:

I will have a mag 9.5 that will push somewhere between 550 to 800 gallons depending on how long my lines will end up.

I believe the mag 9.5 will have a 3/4" output line so the pvc will match that.

In addition I will be setting up a reef only aquarium in a 46 gallon bow front.

Other sources of flow, well, I have the 20 gallon sump (so probably 10 gallons of that will be filled). At this point I have not planned on any additional flow other than this and the over flow.




Oh, in addition; would it be smart to have some one-way valves? I dont know if it is called that but I am referring to traps in the lines so if the pump fails, water cannot travel backwards in the tubs and back to the sump (like heart valves).

 

[youareafever]

what i know is that the check valves, or what you called them "one-way valves" arent to be trusted, algae builds up on them and they fail to work. just drill some siphon breaks in the return pipe and you'll be good.
to make the pvc pipes water tight just use pvc cement and primer to clean it.
as for the water circulation, if your pump is gonna acctually push that much water from the sump then i dont think youll need any power heads but then you got to think of the dead spots that may develop if you only have one or two return lines, unless you get it to point down or something..?

 

[Len]

I like the top right idea, followed by the bottom one. Simple is good IMO.

To keep PVC water tight, you need to use PVC glue and preferably PVC primer before the glue. Apply the glue on both the male end (pipe) and female end (fitting/adapter), insert the PVC, then do a quarter to half twist to "gum" up the glue and make it watertight.

As for check valves, I agree most are terribly unreliable, but I really like the ones that Marine Depot sells (the flapper type). It's the only one that has worked without failing for me.

 

[mr_X]

i have heard the same thing...that check valves are good as long as something doesn't grow, or get in there to stop them from working. the odds of that happening are very good. i would just drill a hole or two just below the water line on your returns. that will stop the siphon quickly in the event of an outtage.
just keep an eye on those holes every once in a while to make sure nothing grows over them. i believe it's alot easier to maintain a few holes in the returns at the very top of the water, than something in-line, way down towards the bottom.

 

[Capslock]

Thanks for all the tips.

I believe I will be going with the bottom design. The mag9.5 has a 3/4" return and well, thats pretty large imo so I will be splitting it into two return lines half way up to 3/4" each.

A few other questions:
First, ok I get the idea of drilling holes but, Well i guess this is a two part question; How do I secure the return lines at the top of the display tank? Esp. I was going to get flexible PVC.

Also, does this image reflect where to properly drill a hole or two? I am not sure with flexible pvc on how to make the end of the return bend at the end to control flow.

 

[shavo]

1 question, with the sump, why is only half going to be filled? that would leave little room for evaporation and you will be topping off alot, most likely every day. I would try to get the sump with more water in it. if you pull the power on the pump it will overflow down into the sump then you can get a line going on how high you can be without it overflowing. plug it back in and see where the level is and tape off on the sump. to set the high line.

just curious why only half way

 

[ChrisRD]

Before deciding to run the sump full, or near full, think about what you're going to do for a skimmer. If you run the water level too deep in the sump, you may have to elevate some in-sump skimmers for them to work correctly. Depending on your stand height, choice of skimmer, etc. you may/may not have room to do this. The little bit of extra water volume you gain may not be worth the headache in some cases.

 

[Capslock]

Well I plan on filling my sump as high as the baffles which go up about 1/2 way to 3/4 of the way. I will only be going as high as the baffles allow. I do intend on making marks as to how high the tank can go in case of power failure.

 

[shavo]

Hey Chris, I am not sure about everybody elses application, but my tank evaporates quite a bit. If I had a 20 gallon tank half filled I would be having to check and top off everyday. If I had a choice (just my preference) I would just put a brick under my skimmer if I needed to elevate. I hear what your saying but what about starving a pump if you don't watch it religiously?

Caps lock, i would suggest knowing the levels and the limits of your water levels incase of power failure, just setting your overflow box too low can cause problems.

 

[mr_X]

yes, drill a hole just under the waterline...just like you drew it.
now, you'll use flexible pvc, but at the top you might use something like this:
http://www.customaquatic.com/customaqua ... EH04003710

that is what you will drill the hole in.
they are secured by the weight of the hose attached to it actually.

 

[brandonberry]

I question the circular flow idea. Most people try to acheive random water flow in their tank rather than a one-directional flow. This can be acheived by crossing the currents of the two outlets. I prefer to have my outlets spaced as far apart as possible and aim both towards the front of the tank allowing the current to bounce off the front glass and cause random swirling motions in the tank. An easy way to assess your flow is to watch what happens when you add a good sized pinch of flake food to the water. You can then easily pick out your areas that have lots of flow and areas that may need more flow.

 

[ChrisRD]

Hey Chris, I am not sure about everybody elses application, but my tank evaporates quite a bit. If I had a 20 gallon tank half filled I would be having to check and top off everyday. If I had a choice (just my preference) I would just put a brick under my skimmer if I needed to elevate. I hear what your saying but what about starving a pump if you don't watch it religiously?

I hear ya - just trying to point out that not everyone has the room for the brick under the skimmer, depending on how tall the skimmer is and how high the stand is. Also, you have to consider proportions here - Capslock is talking about a 20 gallon sump on a 46 gallon display tank, not a 125 gallon display tank like yours. :wink:

I agree that it's good to leave yourself some capacity so the return pump can't run dry too easily. There's a flip side to that, however. If the return pump has access to too much water and you have a problem with the drain/overflow on the main tank, you can end-up with a flood. Personally, I prefer replacing the pump to flood damage. :wink:

IMO it's good to topoff evap daily anyway to keep salinity stable (and pH as well if you're adding kalk or two-part with your evap topoff). Personally I use a litermeter hooked to a large remote reservoir (in the basement) so I don't have to mess with it for weeks at a time.

 

[ChrisRD]

I will have a mag 9.5 that will push somewhere between 550 to 800 gallons depending on how long my lines will end up.

IMO that's a lot of pump for the return on a 46 gallon tank. Unless you're planning on using penductors/eductors on the outlets, you won't get enough in-tank circulation from the return pump alone. You should consider more in-tank circulation from something like a Sureflow Maxijet kit, Hydor Koralia, etc.

You might want to think about a smaller return pump. It will save energy/cost, add less heat to your system water, run quieter, and make it easier to manage noise/microbubbles in the sump. Personally I'm not a big fan of Mags and prefer Ocean Runner or Eheim for submersibles.

 

[shavo]

if he has a large enough overflow box to return water to the sump it wouldn't matter right? it would only bring down the amount that was pumped up right? I agree with you about the tank sizes vs evaporation i think. but we don't know the situation this tank is going to be in. My tank is in the basement and not alot of heat.

Chris I have a question actually, If you have a 20 gallon sump like this one with a heater in it, wouldn't it maybe evaporate more if it was attached to a 46 gallon compared to a 125? just curious what you think about it.
thanks

is it just surface area?

 

[ChrisRD]

if he has a large enough overflow box to return water to the sump it wouldn't matter right? it would only bring down the amount that was pumped up right?

In normal operation yes. In the event of a problem (ie. clogged drain, overflow box loses syphon, etc.) however, I prefer to setup my tanks so that the return pump doesn't have enough water available to it to overtop the main tank.

Chris I have a question actually, If you have a 20 gallon sump like this one with a heater in it, wouldn't it maybe evaporate more if it was attached to a 46 gallon compared to a 125? just curious what you think about it.

Nah, at the typical flow-through rates with reef setups, the heater location shouldn't really effect anything.

is it just surface area?

That's a factor - at least the amount that's exposed to air (ie. not covered). IMO ambient humidity levels, and how many cooling fans you have going are even bigger factors.

For example, I have a 180 FOWLR w/50 gallon sump sitting in my dining room right now running open-top that only evaps a bit more than a gallon per day. No fans running as it doesn't need much cooling...

 

[Capslock]

Thanks for all the conversation about this; its been giving me some good ideas to what I will be doing.

I have my RO filter and I will be hooking that up to the water line today. Sunday I will start putting the water into the tanks.

I will be taking additional pictures of the tanks; I am sure to give you guys an idea on where I am heading with the pump and its lines.