Used tank, what are my options for plumbing?

[zangmann]

Got a hopefully good deal on a 175G starphire tank and need some advice on plumbing such. I also have some concerns with the seals, hopefully someone can help.

So tank has starphire on 3 sides. No top brace around the top, just a thick piece of glass (maybe 12" wide or so) running from back to front.

There are 2 overflows, one on each corner. 2 bulkheads on each. So 2 returns and 2 drains I assume. Each is 3/4". There are also 3 bulkheads that have been drilled but SEALED OFF in the main tank. Two 3/4" in the corners, near the overflows. A single 1.5" in the center of the tank.

I wanted to attempt a closed loop, I assume this is what the tank was drilled for but never made full use of. Would running the 3 bulkheads in the main tank work for this? The 1.5" would be the drain and the 2 3/4" returns? What pump would I run? I was thinking a reeflo dart.

The other 2 overflow returns would return from the sump, any suggestions on a pump for those? Can I/should I somehow add these to the closed loop?

Also I had some concerns about the seals on the tank I noticed a few airbubbles. Take a look and let me know if they are reason for concern.

One of the 3/4" in the corner:
http://www.reefcentral.com/forums/attachment.php?attachmentid=134222&stc=1&d=1292808339

1.5" in the center:
http://www.reefcentral.com/forums/attachment.php?attachmentid=134223&stc=1&d=1292808468

Bubbles? on right side:
http://www.reefcentral.com/forums/attachment.php?attachmentid=134224&stc=1&d=1292808603

Left side, not as bad:
http://www.reefcentral.com/forums/attachment.php?attachmentid=134225&stc=1&d=1292808674

Thanks for looking, I know this is a long post. Any advice is appreciated.

I plan on having primarily SPS, so I'll need around 7500GPH+ for flow. I was going to add a few vortechs to the back wall in addition to the closed loop system.

[zangmann]

Here is a picture of one of the seals along the overflow. What is the hole for?
Can i try to thread a return through there?
http://www.reefcentral.com/forums/attachment.php?attachmentid=134228&stc=1&d=1292809105

Teeth cut out on the overflow, also more of the silicone seals can be seen here.
http://www.reefcentral.com/forums/attachment.php?attachmentid=134229&stc=1&d=1292809273

Thanks for any help!

[Crawfish00]

A pic please of the whole tank pref. From the top

[Crawfish00]

Sorry also 1/2 or 5/8 or 3/4 thick?

[nemosworld]

I would keep the overflows and if yoiu have the space inside, build durso's in side each.
if you can't then i would seal the holes remove the boxes and do a calfo.

[zangmann]

Hopefully these will help, let me know if you need other/larger images.
1/2 inch glass all around. The brace on the top is 18x14x.5.

Left side:
http://reefcentral.com/forums/attachment.php?attachmentid=134316&stc=1&d=1292940706

Right side:
http://reefcentral.com/forums/attachment.php?attachmentid=134318&stc=1&d=1292940880

Top Left:
http://reefcentral.com/forums/attachment.php?attachmentid=134319&stc=1&d=1292940886

Top Right:
http://reefcentral.com/forums/attachment.php?attachmentid=134317&stc=1&d=1292940810

Any suggestions?

[zangmann]

How about this?

Would it be an option to remove the corner overflows and plumb the holes as returns on the closed loop? Run a pipe to the front of the tank for some added flow up there. The other 2 would be returns from the overflow.

Something like this?
http://www.reefcentral.com/forums/attachment.php?attachmentid=134376&stc=1&d=1293030639

I would obviously need to drill holes for an overflow on the back glass, something like a calfo or a glass-holes design.

Is it possible to drill 1/2" glass safely?

[Crawfish00]

Me persoany I concider resealing the tank.. Either do it your self or have someone do it.. It doesn't look to bad but doesn't look good, plus you'll know you'll have no worries.. As for the drilling as long as you use the correct bit and go slow and keep it wet and cool you'll be fine.. Your plans for the plumbing are fine.. I don't know what I'd exactly do I guess it would depend on my lay out..

[Crawfish00]

Come to think of it I don't think I'd put the 3/4" returns in the front.

[zangmann]

Why sell? Because the bubbles on the front seams?

[Clay]

Yes, you can drill 1/2" safely. Remember, it's not cutting glass, it's just grinding a hole.