2 Overflows vs 2 Top Rear Holes

[dlshaw]

I'm going to be ordering my 240g tank soon (60L x 36W x 25H). This tank will be installed into a wall so the rear and sides of the tank will not be seen!! I can get the tank with 2 overflows each overflow contains a 1" return and a 1.5" drain. The cost of the overflows are:

2x Overflows - $150
4x Bulkheads - $60 ($15ea)
2x Covers - $60 ($30ea)
Total Price = $270

However, I can choose to not get the overflows installed and instead have them drill two 1.5" holes on the TOP REAR pane of the glass tank that I would use as skimmers to the sump and I can then use PVC to pipe the return back to the tank over the top of the tank. The cost of this is:

2x 1.5" holes - $50 ($25ea)
2x Bulkheads - $30 ($15ea)
Total Price = $80

It would be a $190 savings to not get the overflows. However, I'm curious which is "best" for the tank.

Pros of not using overflows:
- Cheaper
- More real estate in the tank
- No risk of overflow failure causing entire system to drain

Cons of not using overflows? Would the system perform as well with circulation and skimming? I read this site and it sounded like without using installed overflows he had skimming and flow issues: http://www.petsforum.com/personal/trevor-jones/bulkhead_modifications.html

The place I'm ordering from says with their overflows installed I should get around 3,000 GPH circulation. Would I be able to do this with 2x 1.5" holes at the rear top of the tank as well?

I'd like to go the cheaper route but if its at the cost of poor circulation and/or skimming or other needed items for a reef tank then I'll be forced to get overflows unless there is a 3rd option.

I need to place my order by tomorrow so any advice you have is very much wanted.

Thanks for any help you give!

 

[dlshaw]

Comments plz?

 

[VikeBron]

Are you set on internal overflows or can you do external along the back about half the size of the tank? If I had it to do over, that is the way I would go.

 

[dlshaw]

I don't think they will do overflows off the back side of the tank. And if they did, I don't have the extra room to spare for them as its getting tight as it is

So if my options are the two above would you recommend I get the overflow system or save the extra money as it doesn't make a difference?

 

[VikeBron]

I would then suggest using the overflows in the corners. All the plumbing will be below the tank under the stand rather than behind the tank.

 

[RokleM]

I have an overflow in my 58, and dual holes (top corners) in my 180. By FAR I prefer the holes instead.

This is an older picture of the tank (need to snap some new ones):

 

[dlshaw]

RokleM

Thanks for your input. I'm looking at your picture and it looks like the two holes in the top rear pane of the glass are being used as drains correct? Then you're pumping the water back into the tank over the top (two spouts in the middle there).

Do you have any problems with skimming or flow with this design?

Also, is that a power head on the left and/or right side of the tank or is that piping connected to the drain holes?

 

[gliebig]

dlshaw,

I'm picking up the exact same size tank tomorrow! I ordered mine from glasscages. I hate giving up real estate in my tank, so I'm drilling the back like the tank above. My 125 is set up this way. It works great and saves a lot of room.

 

[kwl1763]

As long as you have a good surface skimmer design to the drain I would drill. Internal overflows are just a waste of space.

 

[dlshaw]

gliebig I too am ordering mine from www.glasscages.com I think I'll go ahead and just drill the back and use the saved money to get a Starphire glass front.

Thanks everyone

 

[RokleM]

<a href=showthread.php?s=&postid=8150462#post8150462 target=_blank>Originally posted</a> by dlshaw
RokleM

Thanks for your input. I'm looking at your picture and it looks like the two holes in the top rear pane of the glass are being used as drains correct? Then you're pumping the water back into the tank over the top (two spouts in the middle there).

Do you have any problems with skimming or flow with this design?

Also, is that a power head on the left and/or right side of the tank or is that piping connected to the drain holes?

I saw and replied to your PM as well, but I'll post here for everyone's benefit:

All of it was schedule 40 white PVC I painted/bound with the Krylon black. Personally I use all SCH80 bulkheads, and only from savko.com (happen to be local, everyone hates us local guys heh). Yes, there is a 3/4" return, which splits into two. I have them blowing in the direction of the drains (yes, one per side) which helps as well to ensure the surface isn't stagnant. The powerheads are Tunze 6100's. They are not connected to the drain. The left one blows across the front of the rock, the right blows across the back. The pulse between 1800 to 3600.

My 58 and 180 both pipe down to a 100 gallon rubbermaid poly sump. I have a GEO skimmer run via a MAG5, with the pump right by the drains from both tanks. It skims like crazy, and even feeding my Anthias 2-4 times a day, I have no nutrient issues that I can really tell.

 

[dlshaw]

Actually, I compromized and got what are called "Califlows" instead. They are overflows but don't go all the way down to the bottom of the tank to save some space but still get the skimming power of overflows.

 

[brackishdude]

http://reefcentral.com/forums/showthread.php?s=&threadid=473152