Odd drilled tank plumbing help

[Caggii]

So I just bought my first tank used thought it was a great price for a 160 turns out it is a 120 but after getting it unloaded and cleaned up a little I realized the holes drilled in the bottom are not like anything I can find people talking about. There are four hole drilled in the bottom of the tank down the centerline. So my question I wanted to set up a sump can I take these 4 holes and maybe use 2 run pipes to a “tank” right next to the main tank and maybe set that up as my overflow into my sump and use the other 2 as returns.

 

[Ron Reefman]

That's a very strange set up. Did you ask the previous owner about how he used these holes?

If you want a more conventional drain and return system, I'd consider getting a piece of glass or sheet PVC cut to just fit inside the tank and use RTV silicone (not the cheap stuff at the hardware store) or 3M Co. 5200 marine adhesive and glue the glass or sheet PVC to the inside of the bottom glass. Then drill the tank to do what you want as drains and returns.

 

[reef r madness]

I had a tank like this...the far left and right holes are the returns...the center holes are the drains to sump..

 

[George Lopez]

This is an old school tank like my dad's old one that was set up for a closed loop system i wouldn't set this up as a sump system personally because if you loose power you run a greater risk of flooding than over a standard drain set up seen in near tanks. Sorry.

 

[PerplexyHexy]

You could use all 4 as returns and hide the pipes in the tank with your rock work... then drill the back yourself for an overflow... just an idea... but you would still have an issue with water back siphoning from return line when power goes out... and thats dangerous having them that low in the water... just an idea... i dont get it... did you not see the holes when you bought it because the sand hid them? That sucks...

 

[Caggii]

This is an old school tank like my dad's old one that was set up for a closed loop system i wouldn't set this up as a sump system personally because if you loose power you run a greater risk of flooding than over a standard drain set up seen in near tanks. Sorry.

Yea I don’t want to just run it to a sump my fear was that it would lose power and drain the tank. My thought is that I would set up a small say 10 gallon tank next to it plumb from the bottom over to the small tank something like this drawing

 

[Montiman]

I would just use the Closed Loop and drill the back. Closed Loops are underutilized IMO

 

[Dom]

You could install 4 threaded bulkheads with threaded PVC plugs to close them and then re-drill for a more current plumbing strategy.

Your substrate will hide the plugs.

 

[Pyrosteve]

I saw a tank like this. It had 4 pvc "stacks" to the water line hidden in the live rock. 2 had strainers and two flexible returns. I kinda liked it. No weir taking up space in the back and could be viewed 360. I have to imagine it would be loud with just strainers tho. Maybe a couple of ol' gurgle busters might help.

 

[Montiman]

This is not meant to house a sump instead it was designed for a closed loop. This is an older filtration technology which is why today I would still use the closed loop but only for circulation. This used to be how everyone did circulation since power head technology hadn't evolved to where it is today yet.

Here is a pick of my planted tank plumbed with a closed loop.

 

[reef r madness]

This is an old school tank like my dad's old one that was set up for a closed loop system i wouldn't set this up as a sump system personally because if you loose power you run a greater risk of flooding than over a standard drain set up seen in near tanks. Sorry.

Yup...I'm pretty sure I had a Fuval 404...under mine..it was the early 90's..till I upgraded to a trickle filter

 

[jsvand5]

I agree with the idea to plug all 4 holes and drill the back. The tank is likely pretty old though and it looks to be very narrow. If it were me I’d just try to resell it and look for something with better dimensions.

 

[chefjpaul]

..

 

[Caggii]

I agree with the idea to plug all 4 holes and drill the back. The tank is likely pretty old though and it looks to be very narrow. If it were me I’d just try to resell it and look for something with better dimensions.

Being new to this large/style I’m not sure what you would consider narrow it’s 6’x21”x20” I really appreciate all the feed back. I will most likely use the closed loop for something maybe a heater and then drill and plumb in an overflow if my idea definitely won’t work.

 

[W1ngz]

As @Ron Reefman said above, I would get some glass and cover the holes using generous amounts of suitable silicone under the patch, and with a bead around the edge.
Make sure to clean the bottom pane thoroughly.
The glass patches :
should be done inside the tank, not under.
should be the same thickness as the bottom pane
overlap around the hole on all sides by at least the diameter of the hole.

Then check to make sure the sides aren't tempered (use the search, there's techniques using a smartphone and sunglasses to verify).
Once you know it's not tempered, you can plan for a more modern overflow with the back or end drilled. Personally I think this tank would make a great peninsula setup!

 

[Montiman]

I don't understand why people would plug the holes. Closed loops are still a great way to provide flow and keep power heads out of the tank. I have been wanting to do a closed loop tank for a while now since the ones I have seen have looked so clean. You certainly can plug the holes but the holes look like a golden opportunity to me. I would deal with adding an overflow and sump separately. You will either need to drill new holes or go over the back.

 

[01xp]

Or you can just put check valves on them and use as returns

 

[George Lopez]

Or you can just put check valves on them and use as returns

Never trust check valves, they will eventually fail. it's not if they fail, it's when they fail.

 

[DaneGer21]

Or you can just put check valves on them and use as returns

Don’t do this

 

[01xp]

Why not? It's just like brakes in your car they don't last forever but you dang well want them. That's my outlook sorry if I misguided the op I would rather have them and fix when they fail and have a little extra safety