Drilling Acrylic Aquarium 4/21/09
Good evening guys and gals,
<Hey.>
I have a question regarding drilling my aquarium. Its a 55 gallon acrylic and I was wondering if there is any way to drill my tank without having to take all the livestock out (fish and coral)?
<Sure there is.>
I was planning on building a sump but would like to avoid pulling everything out considering I just moved and its a pain doing.
<Well, my lawyer advises me to not tell people to drill any tank while it is full. Fact is, I have done this many times without issue...both glass and acrylic. BTW, the acrylic is much easier, just using the regular wood type holesaws.>
Thanks,
Doug
<Welcome, Scott V.>

Re: a couple quick questions... Mis-mix of "reef" life...  Now, Refugium design, glass tank drilling    03/04/09
Hi again!
>Betillo<
Thanks for the quick response to my first email (included with this one)!
<Good>
I had planned on replying earlier, but things have been a little hectic.
So anyway, after reading some of the things you said, I got a little worried and figured I should get rid of the Arrow crab... Ironically, the morning after reading your reply I woke up and wandered over to my tank to find the crab with one of my green chromis in his claw! >=o[
<Yikes!>
So, in response I got him out and took him back to my LFS without a problem. My sea hare is still doing well and readily eats lettuce since there isn't any hair algae in my tank anymore(yay!); it actually just laid a bunch of eggs too! Oh, and as far as the red slime algae removal, it was just by means of a bunch of water changes.
<Okay>
Ok, on to the next part... I finally decided to quit stalling and figure out this sump/refugium ordeal (or try to that is... I've been doing a lot of reading but there's so much info. that it's kind of hard to process it all).
<Take your time... is elementary... well, can be... if taken one aspect and/or step at a time... Anthony Calfo and I have a book that really should be titled "Refugiums" or Marine Invertebrates and the Refugiums They Love... but is titled "Reef Invertebrates"... that is/was an attempt to introduce the several issues in going about these useful biological sumps>
I was able to find a used 30gal. aquarium for $20(which I'm driving down to pick up Friday the 6th) and I'm going to install the divider baffles myself (was thinking of using 1/4" glass since I heard that acrylic doesn't seal well with silicone?).
<You are correct... not well at all>
Or maybe the EPDM pressure locking baffles I found on here instead. I was wondering if you had a suggestion as to the skimmer and return pump...
<Mmm, yes... all my, good friends here, and friends I've yet to meet that have kindly written in and shared are posted already on WWM>
My tank has been up and running for a year and the reason I've been holding out so long on putting in the sump was $$. So I'm a little torn...
I want to go cheaper but obviously want it to work well...(I know it's an oxymoron) lol. I've got 4' from the bottom of the stand to the top of my tank and was thinking of going with two overflow boxes as well. Do you have any suggestions?
<Mmm, yes... again... all choices and opinions I have are posted, and search-able on WWM...>
I've seen a lot of different DIYs as far as skimmers and OF Boxes, but quite honestly I'm not much of a "handyman", so I don't completely trust myself to not mess up and end up wasting money... Any thoughts would be greatly appreciated.
Thanks again,
Betillo
P.S. - Sorry this was so long.
<No worries... IF you can, I would (it's not difficult to do), drill the tank... See Glass-holes.com's site please. And... we'll be chatting! Bob Fenner>

Re: a couple quick questions... Mis-mix of "reef" life... ...  Now, Refugium design, glass tank drilling  03/04/09
Thanks a lot, that was VERY quick!
I checked out the Glass-holes.com website and I really like the look of their overflows... I'm thinking that the 1500 will be good for my 90 since I've got powerheads in the tank already... I am wondering though about the
drilling process though... My tank is full of fish, inverts, corals, rock, and sand. In order to drill for the box, would I need to completely empty the contents of my tank or is it possible to drill say on the width side since I've only got 3.5 inches between the back of my tank and the wall?
<I would drill this and all other systems with the water, livestock out of them... Will send along this query to ScottV, who owns part of the co. for his further input>
<<It is best to empty the tank to drill it. I do not like to recommend to people to drill with water in the tank. That being said, to be perfectly honest with you, I personally drill tanks with the water level dropped only a few inches all the time. A 90 gallon is reasonably thick and one of the easier tanks to get away with this. But here is the real problem: not only do you jeopardize your tank and the livestock within, you do put yourself at risk doing this. There is always a small chance of cracking the glass while drilling....from my experience it is no more likely with water in the tank than an empty tank.
The difference is if it does crack. 99% of the time water will just hemorrhage out of the crack until the tank is
empty. The real risk is you are that small group that has a catastrophic failure from drilling the tank while full. It is possible it could be fatal to you! It is really your choice. But the "correct" answer is to never drill a full tank, tear the thing down to drill. Believe me, having an overflow with adequate throughputs is worth the trouble....you will hate
yourself for starting the project while doing it, but in the end you will be nothing but happy you did.>>
I'd hate to stress the inhabitants let alone stress myself... haha
Thanks again,
Betillo
<Certainly welcome. BobF>
<<Welcome, Scott V.>> 

Possible Megaflow solution?? Plumbing questions?? 12/22/08
Hey guys,
Thanks for the great site!
<Thanks for visiting, hello!>
Here's my current dilemma. I just attempted to install a "Glass-Holes overflow kit" on my 72 bow. They offer a 2x1.5" overflow box that runs 1500gph. The issue here, is that the overflows are predrilled in the rear of the box at aprox 3" apart. I bet you can guess the next part.??
<Hmmm, no.>
Well, I assumed that this sounds logical and worked well in the video on their site.
<And for 1000's of installs around the world.>
So I started drilling as per the attached template and instruction, hole one-ok,...hole two-looked ok. After I wiped away the milky film, I saw a nice thick hair line crack between the 2 holes. After discussing this with a glass company, they said to stay 8" apart min. on holes.
<Based on what? This is quite an arbitrary, ridiculous number. Many factors are involved: glass thickness, hole size, height of the tank, and placement within. The tried and true industry standard is one hole width apart. Take a look at the Oceanic Tech series, many holes drilled mere inches apart.>
Ahh... Hindsight!!
<Really just the risk one takes anytime drilling glass. I do own a stake in the Glass-Holes.com company, do contact us re a refund of your purchase if you wish, we do stand behind what we do!>
So I now have a 72 bow turtle/reptile tank.
OK, now that, that's done, the reason I am writing is I am now looking at a new 90 gallon reef ready tank setup. This new 90 gal RR tank will feed a 30 gallon sump with a 300micron sock, a ASM G2, 2 sets of baffles and a return compartment for internal pump and heater. I may also hang a HOB CPR 19"x4"x12" fuge on the sump as well. I will be keeping softies, LPS, and possibly SPS once I get MH lighting. I can't afford big $$ on a custom tank, and it seems the only option that I have found in the Chicagoland area is the terrific "Megaflow"......
<As you imply, not so "Mega".>
So, I started thinking on how to make the Megaflow, flow better. What is your thought's on this. Using both the 1" drain and the 3/4" return for drains to the sump.
<Honestly common practice with these. Do note that these holes here too are drilled within 8" of each other.>
Then as a return line, I want to use a 3/4" SCWD, and just feed back into the tank with 2- over the rim returns/modular fittings--one on each corner.
<A fine way to route returns.>
So could I assume that total drain to the 30 gal sump is 1- 3/4"(aprox. 300gph) and 1- 1" drain(aprox. 600gph)=total drain to sump approx 900 gallons(this of course does not include any 90's or restrictions)? Is this at all close? If it is not correct, what would you say the flow would be?
<Not really. A 1" will only flow 300 gph safely, with a ¾" about 160 gph.>
What mag pump would you recommend to return via a 1" flex into a 3/4" SCWD, then out to the corners and over into the tank?
<A Mag 5, maybe 7 with a ball valve to control the amount of flow. Neither leaves you with any overflow redundancy.>
Does this idea of using the additional 3/4" drain sound like it's worth the time and effort?
<It is worth it with these things.>
Is there a better way?
<Drill it, even if just one 1.5" drain through the back, within the Megaflow box.>
What is the best way to plumb the 2 feeds? 2 Dursos?
<In this scenario yes.>
Is there any way to get better flow from the "MegaFlows"?
<A new product we/GH are currently working on, not quite there yet.>
Should I stay away from the MegaFlows?
<I in all honestly would.>
Any better, economical options?
<The one you bought IMO, just a bad turn here. Like I say, it can and does happen sometimes whilst drilling glass, or drilling wood/anything for that matter.>
So my other thought to gain some flow in the new 90 gallon megareef tank, besides a single Koralia 3, is to drop a pump into the rather large Megaflow overflow chamber and use the factory Megaflow modular return as an internal closed loop(since I am using the 3/4" return as a drain) . Any thought on this?
<This can work so long as the intake and output of this pump are drilled through the overflow box. Otherwise it will affect the amount of water in the box, creating many other issues.>
What MAG pump would you recommend to use in this Megaflow cavity for return?
<Would not, a traditional closed loop or powerheads are a far better way to go.>
Is there a better pump for less heat then the MAG?
<Eheims, Oceanrunners, among many others.>
Also, what do you think of this setup as a whole(drains--1-3/4", 1-1"------return possible mag 7.5 or 9.5 thru SQWD into 2 returns-----small pump in the Megaflow cavity thru factory return-----Koralia 3 across top of rocks?
<See above.>
Does this sound like enough flow for SPS's? Should I use another Koralia 3, one on each end?
<I would for SPS here.>
What is ideal flow, although-not direct flow, 15x-ph, 20x-ph?
<On the higher end here.>
Why can't AGA see the need for bigger drain?
<A question I have asked for years.>
Thanks for all your time and thoughts on this.
Randy-Chicagoland
<Welcome, best of luck, Scott V.>

Drilling Aquarium (Glass) 9/13/08 I was drilling a 45mm hole for a 1" bulkhead and I got some chipping on the drilling side, not the punch-out. <Rare> It's definitely more chipping than I would have liked to see, it extends slightly beyond the edge of where the bulkhead will fit and I'm worried about possible leaking. <It is quite extensive chipping.> Will silicone applied between the glass and the bulkhead solve this for me? Any other suggestions? <Silicone will work, do be sure to put the bulkhead flange side with the gasket on the opposite side of the chip out.> I also have more holes to drill, can you speculate on the cause of the chip so I don't repeat the same mistake. <Most likely binding, with the bit not perfectly flush. Once the cut is started, even small movements side to side can cause a chip.> I'm using a silicone dam to hold in a pool of water, making sure to back the drill out frequently to keep the water in the hole. I'm also applying very minimal pressure and not drilling too fast. <Do cut yourself a small piece of wood, ¼”-1/2” thick is all you need. Then drill a hole in it so that the glass bit will fit snugly in the wooden template. Lightly clamp or duct tape this to the tank. This little guide will keep the bit from walking when starting the hole, leading to the entire cut being more flush. Do set your drill’s clutch (if it has one) to the lowest setting. If any binding occurs the bit will stop turning rather than chipping or cracking the glass.> Any advice and/or feedback is greatly appreciated. <Have fun with the rest of this product. Do consider going to a glass shop for some scrap and practicing a bit. Even the cheapest bits are good for 10-15 holes, you have some room to play. Scott V.>

Re: Drilling Aquarium (Glass) 9/13/08 9/14/08 Thanks for the suggestions and the advice. Regarding your suggestion for putting the bulkhead in with the flange side and gasket on the non-chipped side; which side is the flange side? The long threaded side? <The end opposite the nut.> Is it ok to put in all the bulkheads that way for conformity or is it better the other way? <Sure, just be sure the gasket is on the same side as the flange.> Also, if the long threaded side will need to be on the outside of the tank, would it be possible to saw the threaded side a little shorter, so as to keep the tank as close to the wall as possible? <Sure, this is normal. Just be sure you leave enough length inside the bulkhead to thread/slip pipe into securely.> Again, thanks for all the help. <Very welcome, Scott V.>

Preparing to drill back wall overflows 12/20/07
Hi Crew,
<Hello David, Scott V. with you again.>
Just cut the overflow towers out of my 120 gallon AGA tank. What a hassle.
<Gutsy too!!>
Next time I will definitely get one of their tanks without drilled bottom glass. Being in Alaska makes a person often take what they can get. I believe I would probably have to pay almost as much to ship an acrylic tank to Fairbanks, Alaska as one would pay for the same tank in the lower 48 states. I have bits due in on Friday. I am putting in two 2" bulkheads, along with a 18.25" x 3.5" x 6" toothed outlet box.
<Excellent.>
I also am getting a Dart pump (Sequence). Advertisements say 3600 gph @ 160 W without given data on ft/sec velocity
<Fairly easy to figure.>
, through a 2" inlet and 1.5" outlet., 12' max head. Definitely cheap energy cost for a lot of circulation. Sequence site says the pump can be dialed down for less gph and longer pump life. I did not check with them the cost for a controller for this task. I know industrial controllers are in the $95-$125 range, as a lot of them are used here in Alaska as Electricity in Fairbanks is $0.14-$0.16 per hour.
<A ball valve on the pump output is all that is needed to accomplish this.>
Three times that cost in the villages and up north.
<Still relatively cheap, try $0.30-0.40 per Kwh!!>
Sure a lot of flow by specs., specially through a 40 gallon sump. I was going to go with two Iwaki 40RLXT's for specs. output of 1200 gph each at 130-140 watts each.
Inlet with wall at about 9" feeding skimmer compartment, putting a TurboFlotor 1000 skimmer (on 3.5-4" high platform) in second , which is the controlled height compartment, over 9"/under/over 6"/under/over 6" - partitions to dissipate skimmer bubbles before 3rd compartment which will have heaters and bulkhead for feeding chiller in 4th compartment will have auto top off, and finally fifth compartment will only have return bulkheads. What do you think about running the Dart or even two Iwaki RXLT40's through a sump this small.
<I have done so in flow tests. I would not do it on an actual system. It is turbulent, noisy, and your baffles will likely not dissipate your micro bubbles before they reach your return.>
The sump should be able to hold the drain down following a power outage, but with not a lot of sump capacity to spare. What do you think of that much flow through a sump.
<I wouldn’t.>
I am think of two Iwakis as dedicated circulation pumps, mainly backup for Dart, with Dart being primary pump fed from overflow (with two 2" bulkheads). I have no room for a larger sump, and I replaced a MegaFlow sump filter to put in a 40 gallon breeder tank. I could go the
opposite way but I am thinking the two Iwaki's (as dedicated circ pumps) opposing each other from each side of the tank would be a better plumbed setup then splitting the return flow out of the Dart to each side of the tank. What do you think it is going to be like with the Dart pushing through a 40 gallon breeder size tank with baffles? Doable, recommendable, too much.
<Just too much from my experience.>
Do you think an Aqua Medic (SP 3000 Niveaumat) auto top off float switch will function with so much flow through its chamber. I could put a portion about 4-6" inches wide next to the float that should stop most disturbances I would think.
<Should work fine.>
Am I way out of line moving so much water through a sump. What is the maximum recommended circulation rate for a reef which will principally hold SPS. I want a lot of flow with very little velocity I would think. Right?
<Flow without a constant direct laminar flow. It seems like the upper limits of SPS tank flow is being increased all the time.>
Please let me know what you think before I start drilling holes!! I am thinking over sized return lines for lessened velocity but high flow. How about bumping up return line of Dart to 2" then Ting down to two 1 1/2" lines put in over the top back of tank to make sure velocity is not to much.
<The water velocity of a DART as a return out of an 1 ½” line is not too bad, two will not be much at all. I would split it into a few ¾” or 1” returns. Also consider using one of the Iwakis as your sump return and the DART as a closed loop. Make the returns adjustable and this will provide you with plenty of the correct kind of flow.>
Sounds kinda off , but?
Thanks Again for your time and help,
David E. Harris
<Welcome, good luck, Scott V.>

Re: Starting Equipment, reef 12/16/07
Ok ... what if I do not feel comfortable drilling my own holes into my glass tank ... it looks like its a pretty tedious process and if I crack the glass I’m out of an aquarium
<It is not really too difficult, basically grinding through, not truly drilling. If you are not comfortable doing it you may want to consider having a glass shop drilling it for you.>
... (what’s the chances of cracking the glass using that method?)
<Always a possibility, but not likely.>
If not ... will a hang on overflow box be ok to use?
<These will work, but they do rely on a siphon. Many use these successfully, just be vigilant with their use.>
Thanks ...
<Welcome, Scott V.>
PS ... I also sent you an email yesterday concerning some lights that I want to purchase.
<This was replied to also.>

Drilling overflows in AGA 12/16/07
Crew,
<Hello David.>
I just ordered an Aquarium Glass Diamond Hole Saw Kit from Diamond Tool King who advertises as one of your sponsors. I already paid for the purchase through PayPal. Do you know if Steve @ Diamond Tool King is legitimate? His prices are excellent, which sort of scares me. I hope his being one of your sponsors, or his advertising on your pages shows he is legitimate.
<No worries, the bits will work fine.>
Here is why I am ordering from him. I am setting up a reef tank starting with a 120 gallon AGA tank. I keep collecting pieces and parts, and reading and continually Reading and rereading. Sorry to say I did not find out about your site until a few weeks ago. I have now repeatedly read that the bulkheads holes are to small too begin to consider the tank a "reef ready Tank".
<Unfortunately the case.>
Yes I will, after tank aging, use the tank principally as a SPS tank, with a small scattering of LPS and even less soft corals. To date I have obtained two Iwaki 40RLXT's, Turboflotor 1000 with Ocean Runner 2700 pump for skimming, Aqualight Pro with two 250-Watt 10,000 K and two 96-Watt PC's. I also have a Megaflow Model 4 Sump, which had to be trimmed to even allow for the TurboFlotor. If I had known that drilling bulkhead holes was not such a great task I would have never gotten the MegaFlow sump. I might still replace it with a glass aquarium and place the baffles where they will work best.
<Whatever it takes to suit your setup, drilling the glass is fairly straightforward.>
I do not plan on using the Bio-balls that came with the sump so it might workout OK. I plan on about 100-150 lbs Live Rock some thing from at least three different areas. Probably large Fiji rock, Tonga shelf and branch rock and some other exotic rock. Now for questions and suggestions. I plan on cutting out the AGA overflow boxes and plugging the small bulkhead holes with plugged bulkheads. Yes I even footed the stupidly high price for two Megaflow overflow kits. Learning can be expensive!
<Learning generally costs something, whether it be time or money!!>
Anyway I plan on two 3 inch holes for 2 inch overflow bulkheads on the tank's back wall, giving a space of at least 3-3.5 inches between hole edge and tank inner wall. Top of 3 inch holes about 2 inches below tanks glass cover ledge.
<Sounds good, perhaps a little bit lower. General rule of thumb is one hole diameter away from any edge. Two inches down should be fine, but three will give you that much more strength in the end. Good choice on overflow size, plenty of capacity here.>
The return locations I am not sure of. With the tanks present setting viewing will be almost entirely through front wall of tank allowing me free rein to drill return holes in side wall which I believe would create better turbulent flow
possibilities due to the opposing flow from returns at both ends of tank. What do you think?
<I am not a fan of drilling for sump returns, at least not too far down due to siphoning issues.>
What with live rock, crushed coral, and live sand/gravel (from GARF) displacement eating up probably 20 gallons of space I figured targeting 2000-2100 gph for flow would probably be acceptable. Shouldn't be able to get around there with my two pumps returning through 1 inch PVC pipe and 1 inch bulkheads.
<Yes.>
I really don't know what would be optimum location for return bulkheads, ie. where on side walls. Middle of front to back? How far from top edge. How did I prevent back siphoning if pump power is loss.
<Yes, this is the problem. Some rely on check valves, but these are not to be trusted to work 100% of the time.>
I also have two Pan World pumps with 1 inch inputs and outputs that I could use for running circulation loop(s) or possibly throttling down one for use with a AquaC EV series skimmer if the TurboFlotor does not work out.
<A closed loop is the way to go here. You will be able to put the intake/return(s) where you would like to optimize flow (perhaps even use the predrilled holes for the intake). This will also allow you to run whatever flow through your sump you desire rather than running the tanks full circulation through.>
I also have a 1/4 HP chiller, lots of Maxi-Jets (900'sand 1200's) and two Wave Masters. Think I need to sale some circulation heads and wavemasters.
<It always seems like you can never have too many extra utility pumps!>
Is there any reason I should even consider putting return bulkhead holes in the tank backwall?
<Over the top will be fine. If you want to drill consider putting it fairly close to the top (again, at least one hole diameter from any edge) and use some Loc-Line for adjustability to minimize siphoning.>
Opinions and suggestions please, before I start drilling, that is if the diamond hole saws show up. Sorry this is so long, but I only have three weeks before school starts up again and I am really antsy to get started on this tank when I am not working.
<Nice project to work on with time off.>
Its been over six years since I last had a reef tank and things seem to keep getting better as time goes on. My last tank was a 125 gallon with a "high" turnover rate of 4 times per hour, 2 Maxi Jet 900's, a 20 gallon sump, 3 250-Watt 650 K halide shop lights, and a Kalkwasser drip. No skimmer, auto top off, CO2 calc reactor, hood with double ended halide bulbs, Actinic Power Compacts, LED moonlights. Things do change!!!
<Wow! They sure do.>
Thanks,
David E. Harris
<Welcome, have fun with your project, Scott V.>

Drilling For A Closed-Loop...Use The Correct Bit Size – 12/12/07
Hello,
<<Hiya Steve>>
I recently purchased a used 100 gallon long tank (60” x 20” x 20”) and am in the planning stage. I would like to bring the tank to my local glass shop to have it drilled for the closed loop. (I really like the neat appearance of a tank with a drilled closed loop & no power heads or PVC to look at.) I will be using a Pan World 50PX-X external pump. I calculate around 775 gph after head loss.
<<Hmm, with this flow rate you should only expect to use a couple ½” nozzles or a single ¾” nozzle for the return, and still have any useful force/strength to the flow. A good rule-of-thumb is to figure 350gph per ½” nozzle and 650gph per ¾” nozzle. Much less than this, and the water won’t exit with enough “force” to have much effect>>
(My return from the sump will be running through a Mag 9.5 and should turn around 570 gph after head loss.) I am planning to drill three holes in the back glass for 1” bulkheads.
<<This size throughput should be fine for the closed-loop, but do consider 1 ½” bulkheads or larger for any “gravity” drain lines>>
One will be an intake with an overflow strainer located dead center, about 1/3 of the way up from the bottom of the tank. (Should I use two intakes instead of one?)
<<One throughput for the pump intake is fine, but to minimize effects from obstructions/blockages, consider using a wye-fitting and “two” bulkhead strainers to supply the intake>>
The other two will be returns drilled 2/3 of the way up 15” from either side. Problem: My local glass shop only has a 2” drill bit and the manufacturer of my bulkheads suggests a 1 ¾” hole.
<<Yes...this is the correct size for the fitting>>
It seems to me that the 2” inch hole may work, but I would like a second opinion on this. I have successfully used a one inch bulkhead in a 2” hole on a 29 gallon tank, but this tank would be much more expensive to replace if a problem occurs.
<<I don’t recommend this, the 2” hole provides too much play/removes too much material behind the rim/lip of the bulkhead for a strong and secure seal. Best to use the correct size bit for the bulkhead. A correct bit can be purchased for around $50...perhaps you can offer to buy the bit and let the glass shop keep it for drilling the holes...>>
I have also considered just drilling one hole for the intake and running the returns over the back, although this is not my first choice.
<<This will work...though I like your first option better>>
Thanks for taking the time to guide me.
<<Hope it helps>>
Your advice is greatly appreciated.
Steve
<<Happy to share. EricR>>

Re: Drilling For A Closed-Loop...Use The Correct Bit Size - 12/12/07
Thanks for the great help!!!
<<Hope it proves worthy>>
I took your advice and ordered the 1 3/4 inch bit.
<<Ah, very good mate>>
I do plan on using 1/2 inch nozzles on the two returns from the closed-loop.
<<Is best>>
Do you think that 775 gph (after head loss) will be sufficient?
<<This will depend much on species kept, placement in the tank, aquascaping… But coupled with the flow from your sump return it will likely be fine>>
I don't want to add powerheads to the tank later.
<<Understood>>
(My inhabitants will be mostly softies that I will transfer from my 55 gallon. Here is a pic of my 55 http://i225.photobucket.com/albums/dd214/SFontana1/55-1.jpg.)
<<Very nice, though if I may… That Rose Anemone should be in a tank of its own… And the Sun Coral colony will require direct feeding for long-term health…>>
The 100 gallon tank I purchased is reef ready.
<<Yes, well…a common misnomer>>
It came with one corner overflow, containing a 1" drain and a 1/2" return.
<<My case in point… These throughputs are hardly adequate on their own for reef type flow, like the term “reef ready” would have you think. Consequently, these throughputs will limit the size return pump to something that will provide no more than 300gph after headloss>>
If both bulkheads were one inch, I would make them both drains. Would it be worth it to convert the 1/2" bulkhead to a drain??
<<Only if you want to maximize the capacity re…though any increase will be very marginal with the addition of a ½” bulkhead drain>>
I guess I could always drill another hole on the opposite side of the tank close to the water line for a second drain and use a strainer fitting.
<<Ahh…now you’re talking!>>
What would you suggest?
<<Another 1 ½” bulkhead to supplement the drain, as you describe>>
Thanks for taking the time to help.
Steve
<<Always a pleasure. Eric Russell>>

Wanted to Share Positive Experience with Recommended Vendor... 12/06/2007
WWM,
<Hi Paul, Mich here.>
I just wanted to share a very positive experience with a vendor that you pointed me towards - glass-holes.com. I have no affiliation with them, other than being a satisfied customer.
<Very good.>
I was looking for internal overflow box for 120g tank, and you suggested I take a look at their website. Mike and the crew at glass-holes.com talked to me a number of times via email and telephone (yes, telephone - nice, personal touch) to help me figure out exactly what I needed. They even called the wholesale-only manufacturer of my tank and talked to the tank builder to find out if the rear wall glass was tempered or not (the manufacturer does a good job of hiding its contact info from the general public... been a while since a Google search was not productive....).
<Resources are good.>
The overflow box they shipped to me was custom ordered and the workmanship was flawless. To anyone comparing overflow boxes built into tanks by the manufacturers vs. something like I got - there is no comparison. No cheap, thin black plastic used. It is 1/4" acrylic, beautifully crafted. The bulkheads supplied are nice and thick (reminds me of the spa jets I put in - thick and sturdy to stand up to high pressure and heat of a 2hp Pentair pump and 400,000 BTU heater). The glass drill bit worked perfectly, and their website had helpful hints that really took a lot of fear out of a DIY project that might make a few queasy (i.e. drilling a glass aquarium). Heck, they also included a t-shirt (I know...free advertising/marketing... but custom t-shirts still cost a couple bucks to produce).
<Yes, both potentially win... that is if you wear the t-shirt.>
You can't beat the prices...about 1/3 to 2/3 the price of the other two custom manufacturers I could find on the web. Their drill bits are the cheapest I could find, and their bulkhead/plumbing prices are very reasonable.
All in all, the folks at WWM should feel more than comfortable sending people over to glass-holes.com. They will treat your viewers right.
<Thank you for sharing your positive experience. I'm sure it will benefit others as well.>
Paul
<Cheers, Mich>

Diamond bits for drilling tanks...    12/5/07
Hi Bob,
<Steve>
I am interested in the top right hand corner ad space. How do I rent this spot?
I sell diamond hole saws and plumbing parts like bulkheads. I have a lot of good customers from you site and some of your staff already.
My EBay seller name is saltydepot and my web site is www.diamondtoolking.com
Thank you,
Steve Peterson
<Neat products... But don't know if this exposure would be appropriate/cost effective. Do you have a short "pro" piece about your business that we could post, link to our sections on the applications of your bits? Will gladly do this. Otherwise, info. re our rates and all can be found here: http://www.wetwebmedia.com/WWMAdminSubWebIndex/wwmsponsors.htm
Cheers, Bob Fenner>

Re: Cursed but drillable Tanks   1/28/07
B
Just an FYI, it is now common practice at most reef clubs to offer tank drilling services even on tanks with tempered glass.  It is usually done very slowly and under wet conditions, but drilling tempered glass is not uncommon and usually done quite successfully, though I have seen failure.  Obviously it will void any warranty.  
M
<Thank you for this update. BobF... still too old to be drillable>
I'd like to drill the tank for an internal overflow and two separate closed loop manifolds.  I spoke with Perfecto and while it will void the warranty they said both the sides and bottom can be drilled.

Drilling Bulkheads - 08/06/05
Dear WWM Crew,
I have decided to get my 30 gallon pre-reef tank drilled and just skip messing with siphon overflows.  (Thanks to reading about all the lovely problems)
<<Excellent!  You'll be much happier for it mate.>>
But I had a few questions.
<<ok>>
First I gathered that tempered glass cannot be drilled but I don't know if my tank is tempered or not.  It is an All-Glass 30 gallon long model (36x12x16) as far as I can gather from the previous owner it was bought new in the mid 90s.  Would you think that this tanks back wall would be tempered?
<<My experience with All-Glass has been that if any, only the bottom pane was/is tempered.  But it's easy enough to contact the company and ask them about this one re the date of manufacture.  I've drilled a few of their tanks (through the sides), both recent and unknown manufacture with no problems (if it is tempered you'll know in a hurry when it "blows out" and scares the bejesus outta ya <G>).  Tanks of recent manufacture should/will be marked if tempered...but then that doesn't help you...>>
If not, I am planning on having (2) 1 3/4" holes drilled to accommodate (2) 1" bulkheads.  I want to have one to each side of the tank and have one drain tee off to a plenum and then connect to the other to feed the sump.  I believe that they should be a minimum of 3" from the top of the tank and 3" from each side.  Is this correct?
<<I just did this very thing for one of my club members...when drilling bulkheads near the edge I recommend placing the outer edge of the holes equidistant from the edge at a distance equal to the diameter of the hole...e.g. - 1 3/4" hole - 1 3/4" spacing, 2 1/2" hole - 2 1/2" spacing, etc...  This will let you get and still maintain strength/integrity of the pane, without guessing at it.>>
I am planning on having between 600-700gph return at first but decided on the larger bulkheads in case I want/need more.  Does this sound okay so far?
<<Problems here I think.  Be cautious of the flow calculators...better to talk to folks/query as you've done here.  The reality is a 1" bulkhead will perform safer, quieter, and with less aggravation/constant fiddling of the plumbing if you only try to push about 300-350 gph per bulkhead.  So...your already maxed out in my opinion.  You'll need to go to a larger bulkhead if you want to turn more water.>>
The tank is for 2 True Percula clowns, Euphyllia glabrescens, Plerogyra sp., Lobophyllia sp., and maybe a Fungia repanda.
<<Ahh...so nice to see you're not going for the usual "reef garden" mix of organisms; you’ll be all the more successful for it>>
Is the flow above reasonable for these species?
<<Yes...be sure to diffuse/spread throughout the tank via multiple outlets.>>
If you have any other thoughts or suggestions please do not hesitate to tell me.
<<Already have <G> >>
I  would rather know now if this setup would work than after I set it up. :)
Best regards,
Andrew        
<<And to you in kind, EricR>>

Re: Drilling Bulkheads - 08/06/05
Dear Eric,
<<Andrew>>
Thanks a lot for your advice, I'll heed it as WWM usually saves me from my own worst ideas.  But I had a few thoughts to run by you.
<<Alrighty>>
If I switched out the 1" bulkheads for some 1.5" bulkheads would this fix my problem of over pumping?  Or, could I make one of the bulkheads a 2" and leave the other as a 1" (the one that tees off to the plenum) and instead of connecting them just run both lines to the sump?
<<A pair of 1 1/2" bulkheads should be fine.  The 1" bulkheads would work, you would just need to size/regulate your return pump (maybe plumb in a gate-valve on the return side) appropriately.  Please have a look through our plumbing FAQs for more on this: http://www.wetwebmedia.com/plumbingmarart.htm>>
Also, I'm not drilling the tank myself but from what you said it is possible to do it yourself?
<<Yes, with the right tools/application.>>
Or would you have a glass company do it?  I have never done it before so I don't know if I want to chance it.
<<First time for everything <G>.  But if you're truly uncomfortable/not handy, it might be best to fine/pay someone else to do it for you.>>
I think that’s everything.
Thanks again,
Andrew
<<Most welcome, EricR>>

Drilling acrylic  1/8/06
Hi,
I bought a custom made acrylic tank that I plan to use as my refugium. I'm going to plumb it inline with one of the outputs from my overflows (~500gph). The tank is made to hold about 27 gallons (20Lx16Wx20T) and is made out of 3/8" acrylic. I plan to use a 1" bulkhead for the inlet and 1.25" bulkhead for the outlet. This will all gravity feed back into my sump and main pump. My question is can I use a typical drill with a hole saw bit for my bulkhead holes?
<Yes>
And do you have any advice for how to drill the holes?
<Yes... Make sure the tool is clean, sharp... go slow... in/out a bit at a time to prevent binding... Some folks advise taping over the area.>
Also, I'm going to put in a 5-6 deep sand bed of sugar sized aragonite and either Gracilaria sp. or Chaetomorpha. Does this seem ideal for my setup?
<... yes. To the extent your plans have been detailed here.>
My main tank is a 220g with live rock, a few corals, and a lot of planktivore feeding fish?
<Don't know... do you? Bob Fenner>
Thanks,
Brandon    

Using Old Rock/Drilling Bulkheads - 08/27/06
Hey guys,
<<Hello (but don't forget the very capable ladies here as well)>>
Thanks again for your time and dedication to our hobby!
<<Is an honor/pleasure to help>>  
I have 2 issues I need help with:
<<Alrighty>>
First, I have read thru the LR section in depth and could not find an exact match to my problem.  I recently purchased a used, and neglected 120 gallon that housed a single clown grouper with several large pieces of rock (it was a FO with rock??).
<<Indeed...that would be a FOWLR (Fish Only With Live Rock)>>
I have kept the rock wet for a few days and can see a few small life forms on it (actual moving little white/clear bug things).
<<Amphipods...probably>>
The rock looks terrible as the tank was neglected and the rock is all dark brown and black.  I will be setting this tank up as a FOWLR and I am thinking that I would like to start over with the rock.  Letting it dry and cleaning it somehow and then letting it cure in the tank for a month or two before adding new fish (pending testing results).
<<Mmm...letting the rock "dry out" will negate its benefits...why not simply keep the rock as it is?  If the color is an issue, it will likely change with improved water quality/lighting>>
Can I get the rock to look better?
<<Depends on what you consider is "better">>
Is it worth losing whatever life it has on it?
<<Not in my opinion>>
It was not really a traditional live rock,
<<...???>>
it has life but it looks very bad.  They are great sized pieces.  The substrate is crushed coral, I would like to reuse it.  It also has black and brown staining on it.
<<This is most likely forms of algae, and will "change" with changes to the environment, as stated>>
Can this also be cleaned?  If so how?
<<Swirling/rinsing with clean saltwater will do the least damage, though you will still loose some biota>>
I don't mind starting over on the rock but will my cleaning methods effect any future fish or possible changes to inverts/coral down the road if I go that direction?
<<Indeed it will...you could give the rock a rinse and a "light" brushing with a soft-bristle brush, or replace it (entirely or in portions) with fresh live rock>>
Second, the tank is a traditional (non RR) tank.  It came with a sump/wet-dry and a HOT overflow.  I am weary of the overflow as I hear that they will eventually fail.
<<Is a good chance, yes...but this risk can be lessened a great deal by employing a redundant system (two siphon overflow boxes) with the first>>
I have once again read on WWM about tank drilling and am thoroughly confused by all the different opinions and issues.
<<Let's see if I can help un-confuse you>>
I would like to drill the rear for 2 sump supplies and 2 sump returns.  Where exactly (how far down and over/apart) do you recommend?
<<Well, if you've established the back glass in non-tempered, I recommend you place the throughputs the width of the hole-to-be-drilled from the edges of the tank, and no closer re to any other throughputs...clear as mud?  For example...a heavy duty 1.5" bulkhead requires a 2.6" hole...the edge of the hole should be no closer than 2.6" from any edge of the tank, or from any edge of another bulkhead hole.  Adjustment of water height in the tank can be accomplished with elbows to raise the level of the pipe outside the tank, or used as adjustable "overflows" within the tank>>
Also what size is best for this size tank if I use a strainer for the supplies down and a directional elbow for the return up?
<<Two 1.5" bulkheads for the drains, and one or two .75" or 1" bulkheads for the returns...or you can simply plumb the returns over the back/ends of the tank>>
Should both the supply and the return have a T installed before the sump?
<<For what purpose?...in what configuration?>>
Also, are there and tips for drilling?
<<Indeed, yes...have a read here:  http://www.wetwebmedia.com/pbholesfaqs.htm >>
I have seen a tank drilled before and they used cooking oil for the lubricant while cutting?  Is this OK?
<<I've always just used water for lubricating the drill bit...works well and is easy to clean up>>
I plan on ordering the needed bits online, any recommended sources?
<<Several choices about...I bought my last bit here: http://www.diamond-drill-bit-and-tool.com/Diamond-Drill/MAIN.htm >>
Any tips?  
<<Heat is your enemy...follow the recommended rotation speed for the size core drill bit used.  The manufacturer states these bits can be used "dry", but use of a lubricant (water) will keep heat down, greatly extend the life of the bit, and speed the drilling process...I use simple 'Play-Dough' to create a "damn" around the area to be drilled and fill/refill with water as needed while drilling.  Also, when possible, use of a drill-press or drill-jig to keep the bit vertical to the glass surface will lessen the chance of damage/fracture of the panel>>
Thanks once again for your help and contribution to our obsession!!!
Randy
<<Quite welcome.  Regards, EricR>>