Plumbing thoughts

[XLwakeboarder]

I have a 180G that I'm getting ready to plumb. I have a 2" drain and 1" return in both corner overflow boxes. I plan on using two little giant return pumps (1 for each return) from my under tank sump. Each one inch return splits into two, 1/2" lock lines at top of overflow box.
Do I go with a 2" stand pipe or reduce down to 1.5"? Then further reduce to 1" sched. 40 pipe to my sump? The 1" drain into sump will then match 1" return lines. Two inch overflow drains seem like overkill to me with only 1" returns but what do I know.
Any thoughts and suggestions will be appreciated.
Thanks

 

[billdogg]

I would not even consider restricting the drain back to the sump. you will be asking for problems. It is way better to have LOTS more drain capacity than return.

 

[gaspasser1]

I totally agree

 

[One Dumm Hikk]

NEVER restrict the drain like that. Its always better to have more drain than return. It has a built in safety factor that way.

 

[johnyjo]

more drain than the return pump can put out
neverk now if the drain might partially clog

 

[XLwakeboarder]

I appreciate the replies. Makes sense when you think about it...

Thanks again

 

[coralfragger101]

You may very well know this already but just because you have two overflows doesn't necessarily mean that you need two return pumps.

Depending on the Little Giants that you are talking about, you could easily put more water into the tank than both of the overflows together could handle.

IMO - you only need one return pump. You should only be looking at putting about 1,000 gph into the tank. One Little Giant could do that.

 

[hebygb]

I agree with Coralfragger... why two pumps? Size one pump to handle all return. The only reason to have a second is for a closed loop.

 

[tank o tang]

I just finished plumbing my 180 to its new stand and am much happier using both the 1" and 3/4" for drains then bringing my return up the back and over the top. Agree, use the second pump for a closed loop or not at all.

 

[ReefEnabler]

but keep the second pump as an emergency back up for when the 1st fails


FWIW, there IS a type of drainage system that calls for restricting the drain, but its another animal.

Its the Herbie drainage method and requires 2 drain pipes (per overflow), one is partially restricted under a full siphon (dead silent) and the other is raised a half inch or inch or so, basically unused and always fully open, ready to take on any extra water if the restricted siphon gets clogged slightly and the tank/overflow starts to overflow.

the secondary emergency drain pipe is CRUCIAL for that design, since it calls for restricting the Siphon drain to about the same speed as the return pump (so no air is getting the line), a difficult equilibrium that can change over time as pipes gunk over etc. This system is nice for the silence, but requires more planning ahead (extra bulkheads and plumbing required!!)

But for anything else I agree with the others that drains should never be restricted and the larger the better. which fitting might a snail shell snag on? good question to ask yourself when planning drains....

my 220 has two 1.5" dursos (one per overflow) that combine to 2" before the sump.


(if you have two overflows you COULD do a herbie drain with only those two drain pipes, but you'd basically lose the surface skimming of one of the overflows and it would become an emergency only overflow, ie huge a waste of space!)

 

[XLwakeboarder]

Thanks guys,
It seems to me by using only one little giant 3mdqx (approx 900gph at 6ft) to to both returns is asking alot. If only one would work I am all for it. I just don't have enough experiance to know for sure. I want to set it up right the first time (not sure that is possible). Sort of get paralysis through analysis with alot of this stuff.
Thanks

 

[ReefEnabler]

If your tank is a nominal "180" then its probaly a bit less than that with glass thickness - overflow volume etc.

but for simplicity sake lets say 180g. Most recommend ~5x turnover of tank volume through the sump. too much more isn't really a benefit.

180 x 5 = 900.

So you're right in the sweet spot with that one pump as a return.


If you want more flow (and you should), try to accomplish it in the form of turnover inside the tank, ie closed loop, or powerheads.

if you try to push too much through the sump it will only make noise and microbubble issues harder to combat, and I don't really see the benefit IMO. some people say too much sump turnover can DECREASE skimmer performance, but I'm not convinced its good or bad for skimming, IMO its just unnecessary. 5x is an ideal turnover through the sump.

now in the tank itself turnovers between 50x - 100x are not unheard of in SPS tanks, usually in the form of closed loop, tunzes, vortecs, modded maxi jets, new koralia magnums etc....

 

[XLwakeboarder]

OK, one pump it is. I do plan on running two vortech mp40s (ive got one so far). I plan on doing the plumbing this weekend.
Thanks for the help.

 

[tank o tang]

Don't forget to take elbow's, tee's, unions, etc. in account for head loss.

 

[XLwakeboarder]

Tank O,
What return pump are you running on your 180?