Plumbing sizes and drainage
 

I'm considering, for multiple reasons, a sump rebuild
Before I do so, and build a shorter height/longer one, I've a drainage issue to solve ...

The reason for this thread is I can't run my Eheim 1262 full out as it overcomes the main drain

I currently have a 1" drain and am using 1" PVC
The bottom of my DT bulkhead (1-1/2" below the glass) is only 5-6" above the level of my sump

A lot of you with under-tank sumps probably have a drop of 12-14" whereas mine is less than 8", and runs quite a ways (6' of lazily sloping horizontal runs and through 4 90s)

Would it be worth my while, with a 1" bulkhead, to step up the drain pipe to 1-1/2" or even 2" and see if there is an improvement in drainage capacity ?
Or is there a disadvantage to larger drainage that I'm not aware of ?

Something else to think about is the angle of the slope as I recall something about there being an ideal magical # that the Romans figured out and is one reason I'm considering a shorter sump - 16 tall instead of 19

Any help is much appreciated

You can increase the standpip size but its still restricted to the size of the bulkhead. The code is 1/4 inch dropper foot of run. Are you sure it's the drain not being able to handle the flow or is it a water can't get into the overflow issue. I had my teeth for the overflow too small and couldn't keep up.

My buddy here in Red Deer has a 300 gal that was drilled out for 1" drains & 1" returns, it was nothing but a major PITA!! I suggested to bushing up to 1.5" right after the bulkheads in the OF & it runs 1000 times better. I have always read that the returns should be smaller then the drains & as you can see by my 300 build all returns are 1" & drains are all 1.5". I have the tank filled right now with fresh water to make sure everything is running correctly & it is all smooth sailing, after a lot of tweaking & tuning.

As for the magic # for downward angle, I think about 2 - 3 degrees is more then enough as you don't want a huge drop on a long run.

To add to Wes's post, when I cut the acrylic out for OF teeth I always cut them 1/4" with 3/8" in between.

Good point about the overflow teeth (is it Wes ?)

My overflow box is an Aqueon Megaflow and it's supposed to handle 750GPH but I'm not seeing that. I can't say for sure what I am actually getting as my pump is not listed on the head loss calculator and I'm not ambitious enough to run my drain into a bucket for 'x' # of minutes

I was thinking the same thing Greg - 2 to 3 degrees down-slope, and Wes' mention of 1/4"/ft is covered in my setup and then some

I'll wait 'till after the holidays to see what others have to say, but I'm really leaning towards trying larger plumbing for a start

My sump is about 30 feet from the tank with very minimal drop ran 2 inch drains and 1.5 inch returns. All the corners were done in double 45s to try and have a gradual corners as well.


Here shows a 1 inch drain would only carry 600 GPh
http://www.reefcentral.com/calc/drain.php

And your's is giving you adequate flow I assume ?

Thanks

I'm going to step up my plumbing after the holiday hubbub dies down

I actually tried something different with my tank, matched the return pump to skimmer size and added more power heads.i had more sump to display flow on my 180 than my 360. So far and is not old enough to notice anything. But to answer the is the plumbing working its yes. I also only have 1 inch bulkheads for returns just bushing to 1.5 immediately and drains are 1.5 bushing to 2 inch and 2 inch standpipe. Talking with a plumber he said dont go less than 3 inch for drain. So I cheaper out and went 2 inch my gate for the herbie is only slightly opened. So I have lots left, dam plumbing and valves and what not was probably 600 bucks :sad:

1" pvc pipe should be able to handle upwards of roughly 900-1000gph of water gravity fed, adding in angles and wyes, valves and so on reduces that amount. Considering your eheim pump has a return of approximately 900gph at 0h I'd suggest you have something other then the actual drain size restricting the flow.

Really makes a difference on how things laid out. Guessing my 1" drain on my fuge maxes out at 200-300gpm.

For drain size take a look at BeanAnimals calculator in his write up as takes in amount of head and type of discharge.

For teeth on a weir like the excel spreadsheet from RDO download section Overflow Capacity Calculator

Thanks for the thoughts and links everyone

It has to be the 1" drain plumbing

The emerg kicks in if I crank it up, so it's not the teeth

I'll change it to 1-1/2"