Overflow boxes vs. pipe drain

[jejton]

What are the advantages/disadvantages to using an overflow box ( built in not hang on ) versus just drilling a hole in the back of a tank and using a pvc elbow with a strainer ?

 

[masterswimmer]

The overflow box will offer more area for surface skimming.
The strainer can get clogged with free floating algae, snails, etc and possibly get blocked enough to cause a flood (unlikely, but possible).

Both methods will work, one just a bit better than the other.

 

[simike]

with the strainer it would be tough to get a good water level, plus with a box you are skimmimg the water surface where all the crap is

look at my tank build to see what i did

 

[Deanos]

I have had consistent water level with a strainer for the last 2 years.

 

[Tonyscoots84]

when i had my 75 gallon up i had a strainer and had no problem either keeping the water level ummmm leveled :biggrin:

 

[jejton]

Are strainers more prone to clogging?

 

[masterswimmer]

Are strainers more prone to clogging?

No question about it. Just due to the nature of how they work and their design they are more prone to clogging. Does this mean it will absolutely, definitely, eventually happen? No. Is it more prone? Yes.

swimmer

 

[MO~IDOL]

I never run a strainer so I don't know. for overflow box u need to run it with a lifter pump 24/7(well at least for me) other wise it'll loose siphon, and the pump die in a year. but my friend running 2 on a 180g. he runs the lifter pump on a timer for 2 Min 2 times a day for 4 years and never lost siphon.

 

[masterswimmer]

I never run a strainer so I don't know. for overflow box u need to run it with a lifter pump 24/7(well at least for me) other wise it'll loose siphon, and the pump die in a year. but my friend running 2 on a 180g. he runs the lifter pump on a timer for 2 Min 2 times a day for 4 years and never lost siphon.

He mentioned he's using:

using an overflow box ( built in not hang on )

not using an external, hangon overflow that would require a lifter pump.....from my interpretation. But I could be totally mistaken.

swimmer

 

[MO~IDOL]

ooh my bad...happy reefing

 

[DallasNYC]

I have a set up with stainers. They do clug up and need to be cleaned more often. I went away for a month and forgot to tell my neighbor who was watching the tank to clean them off. They didn't completely clog up, but enough for a slow trickle to make it over the edge. fortunately, he was smart enough to figure out what the problem was and fixed it pretty quickly.

So that said, with regular maintenance, strainers are fine. My next tank will have a built in overflow.

 

[jejton]

He mentioned he's using:



not using an external, hangon overflow that would require a lifter pump.....from my interpretation. But I could be totally mistaken.

swimmer

Well I'm actually not using anything at the moment. Just doing research, but your interpretation is correct.

Now how do you decide on a pump? Is the pump the limiting factor in the flow rate or is the overflow? Does your pump have to equal, be less than, or greater than the drain rate into the sump ? ( To keep things simple, assume all of the flow is provided by the pump, either through a simple return, manifold, etc. )

 

[DallasNYC]

You want to make sure that your overflow canhandle more than the return pump.

Reef central has a basic calculator to help you design the size of your over flow ...
http://reefcentral.com/calc/drain.php

Of course, you should over design the overflow to deal with any blockage.

 

[masterswimmer]

A 1" overflow will permit 600 gph flow. If your pump is returning more than this, the obvious happens. Water will take the path of least resistance.....over the sides of the tank onto your floor

So bottom line is just like Dallas said, make sure your overflow can handle more than the return flow.

swimmer