No! Drilled The Wrong Size...

[Adam89]

Hey, i finally got the gutts to drill a hole, i wanted to do a 25mm 1 inch overflow but i drilled a 25mm hole not a flaming larger size to fit the pipe!!

So gutted can i increase the side at all?? Or will it crack?

 

[ben1987]

i wouldnt fancy inceasing the size.
Erm cany you use 22mm plumbing through that? You could always have two overflows a 22 and a 25?

 

[keenonfish]

as above or a file designed for ceramic tiles... Talk to your local tile shop (not b&Q!)

 

[mike os]

yes you can redrill with a bigger bit, extra care needed tho as the glass is now weakened (cos of the hole LOL)

dont use a file or grinder.... it will break.

 

[ben1987]

you will never get it round fileing it anyway

 

[xxBarneyxx]

Personally I would put a second overflow in of the same size. You can then use a T join to put them into one larger pipe if you wanted. 2 overflows is always better than 1 anyway

 

[ben1987]

yeah if one was to block then you have one. If you only have one and it blocks you have a wet floor

 

[Adam89]

Well ive sorted it, i just simply sanded down the thread on the tank connector, so now im gunna just run 3/4 inch (22mm internal size). To make extra precautions i will have a accesable roof on my overflowbox and make the water slits very narrow, and that should solve the problem of snails entering and any algea growing indside.

This sould be ok tbh i was contemplating drilling 2 but there two main factors though:

1: ill be running total of 1 1/2" which seems slight over kill on a 140lt cube with a max of 5x turnover and plus the return pipe size is gunna be 1/2" its gunna have to be a higher turn over pump or else it keep draining--- refilling slowly--- draining---- refilling slowly etc etc

2: Ive designed the tank so if either fails no overflow will form.


But one thing is it normal to get the odd chip when the cut out falls out?

 

[andywg]

1: ill be running total of 1 1/2" which seems slight over kill on a 140lt cube with a max of 5x turnover and plus the return pipe size is gunna be 1/2" its gunna have to be a higher turn over pump or else it keep draining--- refilling slowly--- draining---- refilling slowly etc etc

No it won't. Having a much higher capacity of drain than return just means you operate within a larger margin for error. The drain speed is entirely governed by the return pump and nothing else (until the return is too much for the drain).

2: Ive designed the tank so if either fails no overflow will form.

I'm intrigued how you have managed to prevent any problems if the drain gets blocked and the return pump carries on pumping. The only way I can see is to have the water level in the display tank so low that you can fit all the water from the sump return chamber in it which means only adding a fiarly small amount of water to the system through the sump.

I may, of course, be wrong.

But one thing is it normal to get the odd chip when the cut out falls out?

Yeah, I quite often get the odd small imperfection on the circle as the cut out falls. You could probably prevent it by supporting the area to be drilled out, but I never bother and have had no accidents yet.

Andy Tip #56: If you have glass condensation covers keep the pieces cut out from the tanks. Silicone these on to the top condensation ocver to make for easier opening and shutting.

 

[Adam89]

Well tbh im getting the idea that it be safer to do 2 holes....?

Only query then the total overflow size will be 1 1/2 inch so far say the pump runs at 1/2" wont the water level keep going up and down or will it be just not full flow from both overflows... man im confused lol!

What pump should i need for this? height from the pump to tank will be 120cm and will have about 4/5 90 deg elbows but might use flexy hose or a 45deg to not slow down the flow....

 

[xxBarneyxx]

ok if you have two holes on the water line (I assume you drilled the top of the tank and not the bottom?) and fill up the sump and the tank so the water is just below them two hole.

Now when you turn the pump on it will pump the water from the sump to the display and the water level will rise to the overflow. Once the water hits the overflow it will then flow out at exactly the same rate as it is flowing in.

With regards to the pump. Your overflow (with two holes) should be good for upto about 90G per hour. I would say you want to be looking at maybe 40gph (cant remeber how much flow your supposed to have through the sump off the top of my head but I doubt it will be more than this for this size tank).

Not sure what pump to go for but all of them should show you how many GPH it does at certain head height so look for one that can do around 40gph at a head height of 120cm.