My First Time: Drilling, Plumbing, Designing!


New member
The Prologue:

Well, this weekend I was minding my own business driving down the road to my house when I see it... My neighbors are having a moving sale and as I drive by a spot a nice tank sitting in their driveway.

I had no intention of upgrading from my 29G for some time but when you see a good deal, why not?

Ended up purchasing a 55Gallon tank with black iron stand (very sturdy) it's the type that would allow you to view your refugium underneath. $50 after some negnotiation :smokin: and I was on my way.

The project:

Over the next month I plan to accomplish the following....

1) Drill the tank for a closed loop system
2) Refinish the stand with new paint
3) Build a one of a kind "refugium box" (more information below)
4) Buy/purchase a sump/refugium ^^
5) Install the plumbing

Now, I have read a lot of build threads about people drilling tanks and how they do it so I believe I'm all set in that area.

The one thing I'm not entirely sure of is what size holes I should make, how many, and what type of return pump I should use.

I want to eliminate the need for powerheads in the DT so I'm assuming I will need at least 3 return holes?

After I have all the plumbing and holes setup, I will build a "refugium box" which will be placed over my sump/fuge underneath the DT and will be sort of split into two parts. Basically it will just be a black wood box that will hide the sump part, and just show the refugium. I probably didn't explain this well enough and I will post pictures of my design plans tonight.

Could someone please post with information on closed loop setups on 55gallon tanks? I need to know how many holes, what size, and what the best locations would be?


New member
Hi, good find! would love to see some photos.

First you need to make sure the bottom is not tempered glass. If it is you cannot drill it. Only the manufacture will know this info, or their maybe a sticker on the bottom. Worst case you could always drill the back which is most defiantly not tempered.

You could go with 1 drain and 3 returns for the close loop and that should give some pretty good flow. Maybe 1" here depending on the pump you are using.

Buy your bulkheads first get schedule 80, measure the gasket and then drill.

Location depends on the flow you want to create. The drain can be twards the back hidden with some sort of strainer over it.


Then your out takes can be routed through your rock work with pvc, and then loc-line for directional flow.

Hope that helps.


New member
I know the bottom is tempered, Does a closed loop have to have holes in the bottom for return?

Could I just cut one hole in the back for the drain, and have the return pump plumed to the back of the tank as well?

If I have to have a powerhead or two that would be fine, I just really don't want to have an overflow box in view.

What size drain would best too? I'm thinking 1" which would be 600 GPH.

What return pump would you recommend?

Thanks a lot.


New member
Your return will be fine coming through the back glass. On my closed loop I have a one inch drain through the back. It enlarges to 1 1/4". It returns through a manifold I made from PVC. The manifold is made from 1 1/4" Tees. The Tees have 3/4" female threads so they can adapt to Loc-Line. There are four returns with Loc-Line. This is also a good way of creating a gyre vortex. The way mine works is by returning the water on the opposite end of the overflow. The closed loop input is on the left behind the rocks. The returns are on the left at the top blowing towards the overflow for the sump on the right. A power head on the bottom right blowing towards the left will insure a good vortex.

I use a little giant at 1400 gph for mine but I hope to upgrade soon. I also used ball valves with unions on the drain and return.

A good way to make a strainer is by cutting several slits in a piece of PVC. If you drill the drain in the center, you can put a tee in it and have two strainers. Mine is at the end of my tank so I used a 90 with about 16" of 1" PVC with a cap on the end and several slits.

Hope this helps!