Is it drillable?

[gixxer600]

I am going to look at a set-up tomorrow and was wondering how can i tell if a tank is drillable when it is currently running. I do not think it is drilled or reef reary from the pics that i have seen but it is hard to tell. The tank is an Oceanic 135 if that helps and i think the tank is anout 3-5 years old. Thanks for the help in advance.

 

[porpoiseaquatics]

I don't think you can drill an Oceanic bottom. I believe they used tempered glass for that. You should however, be able to drill the back glass. Maybe one of the Oceanic LFSs will chime in to make sure.

 

[cr500_af]

n8life;612650 wrote: A couple of months ago i got a undrilled glass 120 and wasn't sure if it was drillable or not but it was so cheap i decided to chance it figuring that if anything went wrong it would be in the drilling process and I would know to just not use the tank. The drilling went great so I thought I was good until about a month in to having it running and stocked adn one nightr while I was working on some wiring I heard "crack", "crack", "crack" and water started dripping out of the bottom. From what I understand even the cheapest of tanks have the bottom glass tempered. The back may be drillable, but having had a tank with the plumbing going through the back I would never tolerate that level of noise again.

Sounds like plumbing stress. Tempered glass doesn't crack; it shatters like a car window (into glass "crumbs"). IMO a hard-plumbed tank should always use a little bit of Spaflex just to absorb vibration and movement.

Overtightened bulkheads can do this too, but another likely culprit is an unlevel stand... really more "un-flat" than unlevel.

 

[ichthyoid]

cr500_af;612656 wrote: Sounds like plumbing stress. Tempered glass doesn't crack; it shatters like a car window (into glass "crumbs"). IMO a hard-plumbed tank should always use a little bit of Spaflex just to absorb vibration and movement.

Overtightened bulkheads can do this too, but another likely culprit is an unlevel stand... really more "un-flat" than unlevel.

FWIW- Years ago while in college, I ran a game room where we had a bunch of pin ball games. Every once in a while, one of the glass tops would 'explode' into a million pieces. Sometimes this was 'spontaneous', but more often it was during play when someone was banging the machine, and putting stress on them.

 

[gixxer600]

Thanks for the responses. I have drilled tanks before and currently have one that i drilled a return in w/ no issues for about a year now. But with out buying it and then determining if it can be drilled is there a way to look at it and determine. Can i use polarized sunglasses to check with water in it?

 

[lilrobb]

cr500_af;612656 wrote:
Overtightened bulkheads can do this too,

I am not sure how this would work, a bulkhead sandwiches the glass - what would cause it to crack?

 

[markl]

I am not sure how this would work, a bulkhead sandwiches the glass - what would cause it to crack?

Over tightening .

 

[sharkbait]

If you cant drill it at the very least you can do one or two overflow boxes and make it reef ready that way. Don't know if you would want to go that route but its an option if the deal on the tank is really good.

 

[cr500_af]

LilRobb;612712 wrote: I am not sure how this would work, a bulkhead sandwiches the glass - what would cause it to crack?

Mechanically, I don't know... but I've had two people tell me that they had bulkheads installed, and tightened a little more... a little more... crack. Perhaps it was a side load they were introducing during tightening, I have no idea.

 

[gixxer600]

I guess if you were tightening the bulkheads and had a little more pressure on one side more than the other that could crack the glass as well. With it bieng an Oceanic tank it should be drillable at least on the back correct?

 

[grouper therapy]

LilRobb;612712 wrote: I am not sure how this would work, a bulkhead sandwiches the glass - what would cause it to crack?

Probably not from the pressure of the bulkhead itself but more from the pair of adjustable pliers they are using and putting to much uneven/twisting torque on the whole bulkhead .

 

[cr500_af]

gixxer600;612901 wrote: I guess if you were tightening the bulkheads and had a little more pressure on one side more than the other that could crack the glass as well. With it bieng an Oceanic tank it should be drillable at least on the back correct?

Only way to know for sure is to ask the manufacturer. To address an earlier post, you can get some clue from polarized glasses but I wouldn't say it's foolproof.

 

[jennm]

In general, the bottoms are tempered and not drillable. Factory drilled tanks still have tempered bottoms but they drill first, then temper.

In most instances the back/sides are not tempered, and as such, are drillable.

I would not suggest drilling the bottom.

Most tanks come with a sticker somewhere in the bottom trim that states, "Tempered: do not drill". Sometimes the stickers are removed or fall off, but you should have a look to see if it's there - that will answer your question for sure.

Jenn