Thoughts on drilled returns vs going over the rim?

[gabrieltackitt]

Am currently in the design phase of my build and was wondering what everyones opinions are on going over the top rim of the tank vs drilling for returns? why?

 

[lapin]

My ipinion; Its all about the look. If you have a rimless tank you prob do not want pipes showing over the top.

 

[trustmeimalawyer]

I went over the top because 1) I used the extra hole in the overflow box for an emergency drain and 2) didn’t think the risk of cracking the tank was worth it for my particular set up. While it def. wasnt the preferred route, I figured I could live with it until I got a more permanent tank. You can see the white pvc peeking out the back of the left side. Painting it black prob would have camouflaged it a bit more.

 

[lpsouth1978]

For me it comes down to canopy or no canopy. If the tank has a canopy, it will hide the plumbing so going over the top is no big deal. No Canopy and I think the PVC is just unsightly.

 

[Hal3134]

I like drilled because it’s more reliable. Over the top I always worry about losing the siphon. Gravity never stops, so drilled is much more robust. And the failure mode is a flood, which is pretty bad.

 

[stephj03]

Keep in mind you add 1ft of head pressure.for every 90 degree turn ( 3 to go over) in case it impacts return pump requirements

 

[BigHildy53]

I like drilled because it’s more reliable. Over the top I always worry about losing the siphon. Gravity never stops, so drilled is much more robust. And the failure mode is a flood, which is pretty bad.

For my own curiosity, how is loosing the siphon related to the return?

 

[Joekovar]

This is my typical viewing angle. The two columns on the felt diffuse the return that comes in up top. The large column on the right IS my overflow.

It's physically impossible for a power outage to drain my tank over any length of time. I do have to maintain a small siphon kickstart pump and a float switch though.

 

[BigHildy53]

I have over the top return, and I really wish I did duel drilled returns. It's a much cleaner look.

 

[Peace River]

For my own curiosity, how is loosing the siphon related to the return?

I'm pretty sure the comment was directed toward drain plumbing.

 

[Peace River]

IMO the drilled returns are much nicer look and are sturdier, however I like an over-the-top return if I want the flexibility of moving the return location or if it is in a utility-type tank (e.g., breeding, grow-out, etc.). Additionally, some people aren't comfortable drilling holes for the return.

 

[NB Reefer]

Drilling for returns and drain is the safest way to go. As mentioned previously, you can lose the siphon by going over the top, drilled drains and return have no siphon to lose. Depending on how your sump is designed if you lose siphon your tank will stop draining into the sump and the return pump will pump all/most of the water in your sump to your tank. More than likely this will result in a flood. It will also burn out pumps, heaters, etc. in your sump.

I prefer to always use drilled tanks. Over the top has too many disadvantages.

 

[Albertan22]

If you’re designing a new system then 100% go drilled. It looks way better. The only reason not to in my opinion would be because you picked up a used tank that you’re trying to make work.

 

[gabrieltackitt]

Thanks for all the replies. My overflow is already drilled and I will definitely be drilling my return now.

 

[Gareth elliott]

For a diaplay tank unless its a freshwater planted id drill if can. Planted tanks they make a lot of glass pipe so you can see it less. As sumps are a lot less common with co2 injection. Also no salt creep to make the glass look white lol

 

[gabrieltackitt]

For a diaplay tank unless its a freshwater planted id drill if can. Planted tanks they make a lot of glass pipe so you can see it less. As sumps are a lot less common with co2 injection. Also no salt creep to make the glass look white lol

Unrelated question, where did you get the bar that light is hanging from? I have been looking for a way to hang my lights that doesn’t come all the way from the ceiling.

 

[redfishbluefish]

First off, I'm pretty sure the OP is NOT talking about the overflow (i.e. the drain), so losing siphon is not an issue. The OP is talking about the return line(s) coming up from the sump to the DT.

My preference is over the top. The reason is that drilled drops the return down into the DT at least an inch or so. So when the pumps get turned off, all that water drains back into the sump...too much. I know you're going to say use check valves. Check valves just put off your eventual flood....they will fail. So my vote is over the top. I did it with my tank (and have a canopy) and actually still didn't want to see the pipes....so I covered them up.

Pipes exposed:

Pipes covered:

 

[NS Mike D]

I've had both. I like my old 100gal that had two corner weirs with the drain pipes drilled through the bottom. Clean look, fairly quiet and extremely reliable.

I made and over the top for my 29gal aqueon as I could not confirm if the glass was tempered so I didn't want to take risk of drilling. I was concerned about the siphon. It's been two years now and aside from my intentionally interfering, the siphon had never broken on its own, and that includes turning off the pumps every day to feed.

While I am proud of my DIY over the top, I'd drill if I could.

 

[acan-man]

Drilling sounds way scarier than it is. I picked up a used tank a few months ago and a bit from Amazon. Watched fishofhex and king of DIY videos. Test drilled on a piece of plexy, then used that as a guide. Total time not even 10 minutes and totally worth it. Also with a bulkhead, easy transition into to loc line for split head return.

 

[ca1ore]

Pros and cons ....

As somebody finally noted, since you cannot get the return hole close enough to the top rim, you end up having to deal with excessive drain down. Either use a check and hope it works, oversize the sump or add extra pvc inside the tank. None are great options frankly, so I went over the rim on my current 450. Use black pvc and it’s really not noticible. Maybe a rimless tank changes the calculation .... maybe.