Over the rim return lines, or drilled?

[itsTD]

I am working on plumbing my new tank right now. I am trying to decide between drilling my return lines into the glass and using bulkheads, or just going over the top with PVC. What is everyone’s thoughts? Drilling would look a lot nicer, but I’m not sure I want to worry about drilling through the tank. I’ve heard some horror stories about people having issues with their bulkheads leaking. I’ll be using loc-line regardless. For reference, this is for a 75 gallon tank. All thoughts are appreciated, thanks!

 

[pjleathal]

I think it just comes down to preference. Personally I've had both and I like the drilled returns. They make the tank look cleaner. But your right they can leak. But so can the bulkheads for the overflow. IMHO I prefer drilled returns.

 

[mfinn]

I've done it both ways and IMO there is no difference with performance.
I had my current 240 drilled for a return line.
My 66 isn't drilled.
If you are not comfortable drilling glass, then over the top works .

 

[exnisstech]

Are you using a hob overflow? If not then your most likely going to have bulk heads already so I would drill for the returns. Drilled is cleaner looking and one less thing to work around if you want a lid.

 

[skey44]

I’m planning over the top for my frag tank. What is the best method to go over the top? I was planning on using 90’s to make it up and over and then hard pvc down the back of the stand, converting to flexible tubing via a barb fitting before the sump transition.

My tank is pre drilled but plan on using the 3/4” drain for the herbie siphon drain and the 1” as the emergency drain.

 

[BryanM]

definitely just personal preference.

 

[UncommonSense]

I think that there are several structural factors to consider here, which haven’t been addressed!

A: how thick is the tank’s glass/acrylic?

B: is the tank rimless?

C: how many holes in that pane? (“Returns” implies at least two holes… what about overflow holes?)

D: how confident/experienced are you drilling acrylic/glass?

E: how are you plumbing these bulkheads?


F: considering all these factors; is it worth drilling the tank, over just getting a pair of cheap ABS hang on return nozzles, or making your own PVC ones?

 

[twentyleagues]

I think that there are several structural factors to consider here, which haven’t been addressed!

A: how thick is the tank’s glass/acrylic?

B: is the tank rimless?

C: how many holes in that pane? (“Returns” implies at least two holes… what about overflow holes?)

D: how confident/experienced are you drilling acrylic/glass?

E: how are you plumbing these bulkheads?


F: considering all these factors; is it worth drilling the tank, over just getting a pair of cheap ABS hang on return nozzles, or making your own PVC ones?

Your posts are far too logical with many good points. Who are you? lol I guess the name says it all.

Only point anyone has not addressed yet is, is the tank or the pane of glass you intend on drilling even drillable? Could be tempered. Has this been checked? I had a 75g I drilled common 75g that petco sells the side panels were tempered the long panels were not. I only checked one of the long panes got most of the way through the short and it shattered. That was dumb I admit but I wanted to set it up peninsula style. Why didnt I check the short ones? To me it didnt make sense the long would be not tempered and the short would. Still does not make sense to me. Just fyi they could have any combo of the above or the whole thing or none at all. Got that straight from the manufacturer Aqueon they just get precut glass in bulk to slap these together anymore sometimes it comes in as tempered sometimes not. They didnt say it that way, I extrapolated that from their word soup.

 

[Pntbll687]

I would go over the top, simply because you add/subtract and change flow if you want more easily than with a bulkhead.

Another think to think about, if you are going with a bulkhead, PLEASE support the return lines so it's not pulling on the bulkhead 24/7

 

[PPBlimpy]

Preference really. i don't mind bulkheads.

I have an acrylic tank, have 5 x 1" BH holes drilled in the bottom for closed loop and 5 on the back 4 x 1.5" BH for overflows and 1 x 2" BH for closed loop. But also will be going over the top for my returns.

I prefer over the top for returns so I can put in an anti-syphon hole and not have to run a 1 way valve.

 

[itsTD]

thanks everyone! I appreciate the feedback. What an amazing community of reef enthusiasts. I am still very new to the hobby. To answer a lot of your questions, I will be installing a fiji cube overflow, so I’m already drilling into the tank. I did verify that my back panel is in fact not tempered. Since I am already drilling the overflow, I might as well just drill 2 returns. I have a pretty good plumbing background, so the drilling and plumbing shouldn’t be an issue. My main concern is the BH’s leaking. I wonder if I used some sort of aquarium safe silicone grease (similar to swimming pool grease /lubrication for rubber gaskets) would be good to dab onto the BH gasket to help create a super good seal. Has anyone tried this? Anyway, appreciate everyone’s feedback! Lastly, if I am drilling 3/4” returns for bulkheads, I would need to buy a 1.5” diamond hole saw bit, right?

 

[UncommonSense]

thanks everyone! I appreciate the feedback. What an amazing community of reef enthusiasts. I am still very new to the hobby. To answer a lot of your questions, I will be installing a fiji cube overflow, so I’m already drilling into the tank. I did verify that my back panel is in fact not tempered. Since I am already drilling the overflow, I might as well just drill 2 returns. I have a pretty good plumbing background, so the drilling and plumbing shouldn’t be an issue. My main concern is the BH’s leaking. I wonder if I used some sort of aquarium safe silicone grease (similar to swimming pool grease /lubrication for rubber gaskets) would be good to dab onto the BH gasket to help create a super good seal. Has anyone tried this? Anyway, appreciate everyone’s feedback! Lastly, if I am drilling 3/4” returns for bulkheads, I would need to buy a 1.5” diamond hole saw bit, right?

There are aquarium safe silicone o-ring lubricants!

Yes, they do work! Worst-case; you can always lay a bead of silicone aquarium sealant on both sides of the gasket during install!

I recommend picking out your bulkheads before you order your diamond hole saw (BH dimensions) ; you want the hole saw 1-3mm oversized for the BH!

Schedule 80 bulkheads are the way to go if you don’t want to worry about them for years down the road!

 

[itsTD]

Great thanks! Looks like this would work for silicone grease. Could you confirm? thank you so much!!

https://a.co/d/g3rnrhf

 

[UncommonSense]

Great thanks! Looks like this would work for silicone grease. Could you confirm? thank you so much!!

https://a.co/d/g3rnrhf

I don’t see any reason that wouldn’t work! It doesn’t list specific ingredients; but then again, neither do the overpriced .5-1oz bottles of aquarium o-ring lubricating silicone…

 

[UncommonSense]

Here’s a photo of my ancient 75g freshwater DT, which was drilled for 2x drains, 1x return, all 1” SCH80… it has since become the sump under its 180g replacement! — hopefully it gives you some ideas for hole placement!

 

[itsTD]

Here’s a photo of my ancient 75g freshwater DT, which was drilled for 2x drains, 1x return, all 1” SCH80… it has since become the sump under its 180g replacement! — hopefully it gives you some ideas for hole placement!

Wow, love it! Thanks for the guidance and visual. I’m excited to get it going!

 

[UncommonSense]

Happy to help! Would you like any tips on the glass drilling process?

 

[itsTD]

Happy to help! Would you like any tips on the glass drilling process?

I’ve done some research. Keep water on it, drill slow, let the drill do all the work, be patient most importantly! Anything I’m missing?

 

[UncommonSense]

I’ve done some research. Keep water on it, drill slow, let the drill do all the work, be patient most importantly! Anything I’m missing?

You got it!

One thing I often see missed: drill clutch!

— almost all cordless drills have a clutch setting, definitely use it! (I recall around 7-10-ish lbs slip being the happy place)

Regarding the water? I prefer using a continuous trickle of water over the putty dam technique! Flowing water clears the abrasive glass dust away! — the dam method makes you use the water/glass slurry as a lubricant, which seems to wear out the diamond hole saw faster!

Because you’re using your drill clutch, low speed drilling is only important at the start, and finish of each hole; you can run medium to high speed through the meat of the cut!

Do you have a drill template in mind? My last overflow kit (shadow) came with a ~1/4” thick double wall extruded styrene drill template, which worked great to hold the diamond hole saw right where I wanted it! — a piece of plywood, or other dimensionally stable material works great as a guide too, just let the glass dust out!

I drilled two ~2.5” holes for the aforementioned overflow in my 180g, it took me 45 mins straight to cut them both through 1/2” glass (wore out my hole saw too!)! — it could have gone twice as fast, but I was being very cautious!

 

[itsTD]

Wow, that’s a lot of good tips I never knew about! Thank you my friend. Yes, my fiji cube comes with a guide which is nice. But I’ll need to get creative for my returns since they are a different size… so I’ll have to rig up a guide with plywood or something similar like you mentioned to keep that bit from slipping around!

Hey another random question while I have you here. When I go from ABS bulkhead slip to PVC from the overflow drain and the returns, is PVC glue ok? I have been reading that since the bulkheads are not pvc but rather ABS, you need a special glue that bonds the pvc to the ABS. What are your thoughts on this, any experience?

Appreciate ya!