# What does predrilled refer to??



## Hannibal (Dec 2, 2002)

I was wondering if anyone could suggest a site I could look this stuff up on or if you could explain it to me. My brother saw some tank this weekend he liked in a Hardware store and it was only like 75 gallons but it was some outrageous amount of money. I asked if it was predrilled. And he asked what that meant. I really dont even think I know. I know its more expensive. I dont know if it has to do with the tank stand, or whether predrilled has to do with like the water removal or using a protein skimmer, or a sump or something. Can you explain this to me, or give me a site or tell me why it is so expensive? I would like to be able to explain this to my brother as well.


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## Sir Nathan XXI (Jan 29, 2003)

predrilled means the tank has holes drilled in the glass, usually the bottom, then a wall like a dam is build around that to maintain tank water height, one hole if for a drain the other is for your water return line, this setup is to connect to sump filters,

here is a pic of it









pic is from all-glass.com


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## Xenon (Nov 15, 2002)

Good explanation, with pic.


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## Hannibal (Dec 2, 2002)

sump filets..... I mean is this so you arent directly adding water right into your tank?? its for like adding water through the sump. and does this have to do with something I heard about how you dont even need a heater in the tank, you could have hte heater in another place... like this sump and that would heat the water for you since it is constantly taking out and returning the water from the sump?

What are the benifits of this? Is it necessary? does it recreate the instances in the wild or what?

Im glad you answered Nate I was just gonna PM you about it, but I thought a discussion would be best.


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## Sir Nathan XXI (Jan 29, 2003)

What happens is this

power off on pump: you fill tank to its full hieght, then you fill sump up a little past top of pump

turn pump on: water is poured into the tank via pump from sump, water then overflows into the dam section and is drained into the sump,

so basically its a continous trading of water back and forth, but continuous

a sump is a holding chamber, basically another tank, where people put heaters, skimmers, wet-drys, chemcial filtration, auto-water changers, etc etc


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## RhomZilla (Feb 12, 2003)

Sir Nathan XXI said:


> predrilled means the tank has holes drilled in the glass, usually the bottom, then a wall like a dam is build around that to maintain tank water height, one hole if for a drain the other is for your water return line, this setup is to connect to sump filters,
> 
> here is a pic of it
> 
> ...


 I wouldn't/couldn't have explained it better.


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