DIY 75 Gallon Sump

SnookNRedZ · May 15, 2018

So I ended up buying a used Marineland 75 gallon tank on Craigslist last weekend and I also found some acrylic on Amazon that arrived today. I bought (2) 18”X24” 1/4” sheets and one 1/2” sheet same dimensions for the baffles. They arrived super fast, I was surprised. I’m gonna make a traditional DIY style sump like I have running on my system now, and a previous system I had set up. I have no plans on what it will be a sump for, perhaps a 180 or something like that in the distant future. Who knows. Heres the cleaning photo at my shop.

I plan on making a 11.2 gallon skimmer section: 12”Hx18”Wx12”L (1/4” sheet)

1.6 gallon baffle area if 1” separation between both baffles for a 10”Hx18”Wx2”L (1/4”)

7.8 gallon return section 10”Hx18”Wx10”L (1/4”)

35.5 gallon refugium section (1/2” sheet) 19”Hx18”Wx24”L

Total sump volume will linger right around 56.1 gallons

I will cut the acrylic at the shop tomorrow, but won’t end up siliconing anything for a while, I’ll be out of town for work for a bit building staging for a country concert at Daytona speedway for a week. Once I’ve got some free time, that’ll happen. I’ll make sure to add pics if anyone’s interested in the progression.

Palyzoa · May 16, 2018

Correct me if I'm wrong but silicone doesn't like to stick to acrylic very well. You might be better off using glass baffles for the build. I know people have used acrylic for baffles on glass sumps before but I don't know how long it would hold up secure. I'd hate for you to get everything all set up and running on your new tank just to have your sump fail. At least this is what I've always heard... Anyways, I'm actually going to be building a sump soon myself and will be searching for different ideas so I'm going to follow this thread. Looking forward to your build!

SnookNRedZ · May 16, 2018

This will be the 3rd sump I’ve built this way. I use a copeous amount of silicone and I’ve never have any issues. Thanks for the concern tho.

SnookNRedZ · May 16, 2018

If I was trying to construct a water tight aquarium out of acrylic, you’re right, silicone wouldn’t do the job, but as I’m merely using the acrylic as baffles. The water pressure inside will help hold the them together. The fuge area would be my main concern, which is why I went with 1/2” thick acrylic, and will use a generous amount on the side opposite the water. So it will act like a wedge of sorts just holding it in place vs create an entire water tight seal.

I noticed in my 40 breeder I made a sump, my acrylic bowed a bit in my fuge compartment. That’s why this build I stepped up the thickness of that compartment. I have all the faith in the world that nothing will fall apart on me. It’s not going on a set up right away either. Like this is for a far far off build that will be in a house that I haven’t even began looking for yet. So I have time.

SnookNRedZ · May 16, 2018

This is my current sump. Made from a 20 long. It’s around 13 gallons of water.

If you check out the bottom right (fuge) of my 40 sump, it’s bowing pretty bad. the silicone never budged on me because I used so much to where I don’t really care if it’s pretty. Lol I’ve done it enough now to where I can make the seam look actually halfway decent. But practice makes perfect.

SnookNRedZ · May 25, 2018

The baffles look like poo, but so long as they can hold up, I haven’t the care in the world. The fuge isn’t too too bad as far as the silicone goes. I used one whole tube of silicone for the job, and I bought two, so if the silicone doesn’t hold I’ll jusy clean the acrylic and give it another go. Won’t be actually used for a while, so I’m in zero hurry.

SnookNRedZ · May 25, 2018

Now, to find a tank for this to filter... lol

SnookNRedZ · May 28, 2018

So my OCD tendencies got the best of me, and I decided to redo the skimmer and bubble baffle sections. I cleaned up the silicone the best I could, and it looks way better. On a side note, it took quite a lot of force to remove both acrylic sheets. Like way more than I had anticipated. I have all the faith in the world now that I’ve actually pulled and tugged at them that they’ll be fine when actually set up.

The amount of force it took to remove the baffles really surprised me. I was worried after reading the comment that it wouldn’t hold, because this is the largest sump I’ve attenpted this method with. And the force of water pushing on the fuge was a bit of a concern. Until I removed the skimmer section and then felt how stought it was. I’m pretty happy overall. Re ran the numbers too and it’s around 50 gallons. The other estimate was with outside dimensions. The fuge alone is 30.5 gallons which is awesome. My mangrove tree will be able to grow out and mature, and I could possibly do a sea horse in there

who knows!

Marc88 · May 28, 2018

How loud is the water sound from your refugium baffle?

SnookNRedZ · May 28, 2018

With the hose acting as my water pump, the sound was a slight trickle. I plan on having a pump that is controlled by a valve feeding it ultimately. So that there is not too much flow making it noisey. Once the acrylic has time to get algae on it... it will also dampen the sound. At least that’s what I’ve seen happen in the past.

Marc88 · May 29, 2018

Ah...nice build so far. keep up the good work.

SnookNRedZ · May 29, 2018

Marc88 said:
Ah...nice build so far. keep up the good work.

Thank you Marc. I love projects like this, and as stated before this is my 3rd time making one. So practice definitely helps out! Once I have my own home and free myself of apartment life, this will be going on either a 180 or a 220. I'm not sure yet. Here are the exact measurements of the compartments.

--------------L x W x H-----------------
Skimmer -11 x 17.25 x 12 - 9.9 gallons
Bubble trap - 2.5 x 17.25 x 10 - 1.9 gallons
Return - 10.5 x 17.25 x 10 - 7.8 gallons
Refugium - 22 x 17.25 x 18.5 - 30.4 gallons

SnookNRedZ · May 30, 2018

The skimmer and bubble trap passed the leak test today. I’m pleased at how it looks too, it’s way cleaner than my first attempt. Ive been thinking that I really want to move away from having this sump under its display. This will allow me to clean it and my equipment more easily. Also making my fuge easier to see , because I kind of want to do a nice looking display fuge. With macro algeas, mangroves, some shrimps & crabs, maybe a sea horse in the future. Who knows, I just want to take full advantage of having a nice 30 gallon fuge to work with. I mean it alone has a little more water than my entire nano system I have right now. Lol display and sump combined!

SnookNRedZ · Oct 24, 2018

Marc88 said:
How loud is the water sound from your refugium baffle?

Ive had this tank wet with saltwater now for about 2.5 weeks, and at first, the sound of a MJ-1200 with flexible tubing as the return was pretty bad. but after a week or so, the baffle waterfalls have formed a uniform and consistent flow pattern down the acrylic and is almost silent, the most noise i hear now is just from the pump itself, the water isn't near as bad as it first was.

SnookNRedZ · Dec 19, 2018

It’s been roughly a month or so since this sump has been filtering a 75 gallon AGA RR. I couldn’t be more pleased with it. I hope to have the refugium going not too far down the road. I think it will look pretty nice having a rather large refugium. It’s easentially 1/2 my display volume. Which will hopefully turn out beneficial in the long run as well. My skimmer stand is (7) 1.5” pvc cut to 5” zip tied together. Seems to be doing just fine. I have a BRS order with some ceramic media and a mesh bag coming Friday & I plan on stuffing the pvc with the media and putting the mesh around it to give it two purposes, house some surface area for bacteria as well as lift the skimmer up to a height of 7”.

On a side note I strung up 30lb test florocarbon fishing line to my filter sock and an eyelet screw in my stand to hold it in place in a manor where it filters properly. I have my eye on one of the new roller mats that could be added in the future. Maybe around RAP or MACNA next year

Jon Fishman · Apr 16, 2019

Following along, and also stealing your dimensions so I can setup my 75 as a sump!

From the picture I'm having trouble seeing how you have it..... The Skimmer is in the same chamber as the return? The middle section is??? That entire section on the right is gonna be a fuge?!?!

EDIT, no, I see the return pump in that middle section now that I look.....

SnookNRedZ · Apr 17, 2019

Jon Fishman said:
Following along, and also stealing your dimensions so I can setup my 75 as a sump!

From the picture I'm having trouble seeing how you have it..... The Skimmer is in the same chamber as the return? The middle section is??? That entire section on the right is gonna be a fuge?!?!

EDIT, no, I see the return pump in that middle section now that I look.....

It’s the most basic layout of a DIY sump. It works! [Skimmer ||| return | fuge]

Yeah the entire right half of the tank is my fuge. It’s not quite where I’d like it to be, I’m gonna add some sand here shortly. Lit up by a kessil.

I have a build thread on here as well if you wanna check it out. I might have some other photos in there; but here’s a couple recent ones.

Jon Fishman · Apr 17, 2019

I was about to ask 1,000 questions, but I'll check out the build thread! thanks!

Zdaniels · Jan 30, 2023

SnookNRedZ said:
So my OCD tendencies got the best of me, and I decided to redo the skimmer and bubble baffle sections. I cleaned up the silicone the best I could, and it looks way better. On a side note, it took quite a lot of force to remove both acrylic sheets. Like way more than I had anticipated. I have all the faith in the world now that I’ve actually pulled and tugged at them that they’ll be fine when actually set up.

The amount of force it took to remove the baffles really surprised me. I was worried after reading the comment that it wouldn’t hold, because this is the largest sump I’ve attenpted this method with. And the force of water pushing on the fuge was a bit of a concern. Until I removed the skimmer section and then felt how stought it was. I’m pretty happy overall. Re ran the numbers too and it’s around 50 gallons. The other estimate was with outside dimensions. The fuge alone is 30.5 gallons which is awesome. My mangrove tree will be able to grow out and mature, and I could possibly do a sea horse in there who knows!

Where does the display tank drain to? The protien chamber?