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Tank renovation (not for the faint of bandwidth)


Dec 22, 2004
In the downtime between tank inhabitants, I renovated the plumbing on my 75 gallon tank. Pictures are a lot easier now following Black Friday :smile:

The previous configuration can be seen in all its glory in the following thread:

Tank photos - finally!

That configuration was basically a proof-of-concept. Since the basic idea worked, I kept it but cleaned up the plumbing and made things a little smoother.


The tank looks nice in the dark. Recap: Oceanic 75 gallon tank with a custom external glass overflow. Primary biofilter is a DIY wet/dry made from a 5-gallon bucket, containing about 4 gallons of bioballs (visible to the right). Other filtration includes an AM Turboflotor 1000 protein skimmer, a filter sock and chaetomorpha.



Two images of the spraybar that returns water to the display from the sump. The Mag-7 pump manages between about 350 and 400 gph. The spraybar is octo-proofed with fiberglass window screen and zip-ties.


Here's an image of the overflow and the biofilter. The overflow was made by drilling 24 small slots near the top of the tank and building a glass box around them. Two bulkhead holes in the bottom of the overflow box accommodate standpipes.

The line going into the biofilter contains a ball valve to throttle the flow and a filter sock to prevent detritus from decaying inside the filter.


Here's a closeup of the slots as seen from inside. Octoproofing is more fiberglass window screen, sandwiched behind a frame of rigid plastic and held in place with zip ties. A previous incarnation just had the window screen and zip ties, but it would be too easy for an octopus to peel the screen back and climb through. The plastic frame won't make that impossible, but much less likely.


Here are the slots from just outside the tank. You can see the backs of the zip ties.

A short (1 mb) video of the overflow at work.


This is what I call a linear plumbing diagram. The plumbing takes so many crazy twists and turns, sometimes--like Eagon Spangler's slinkey--its easier just to see it straightened.

The bypass line coming from the overflow is an emergency line in case the main line is plugged. The bypass line coming out of the filter (the "wet/dry overflow line") keeps the water level in the filter a bit lower than it otherwise would be. The ball valve on that line keeps just enough water in the bottom of the filter to keep it from "flushing."


Here are the three lines coming into the stand. In the system's previous incarnation, a buttload of 45 degree elbows maneuvered these lines around the back of the stand. This time I shored up the inside of the stand with some 1x4s and drilled straight through. Someday when I have a house and a basement sump the PVC can run straight down from the overflow into the stand and won't be an eyesore.


Here's the view of the lines coming in from the inside. The line in the right is the wet/dry overflow line. The one on the top left is the emergency bypass line, and the one right below it is the skimmer bypass line. You can see the branch coming up and then down into the sump carrying the flow from the filter that the skimmer can't take. The air line tube is the auto-topoff.


Here's a view of the sump. You can see the skimmer and its Oceanrunner needlewheel pump amidst the mess of plumbing. On the left-hand side is the refugium and return pump.

The money shot.

Skimmers need to have their necks cleaned a lot more often than most people do. My favorite thing about the 'flotor is the neck is completely in the cup so I can easily clean it whenever I empty the cup.


Here's the refugium section. You can see the chaetomorpha lives spread out above an eggcrate table. This is a better way to keep it than in a big clump, where the inside stuff doesn't get any light and discorporates, releasing nitrates, etc, back in the water. I have the refugium light on a reverse photo period to keep the pH stable. Also in this section are two float switches for the auto-topoff system, which helps keep the salinity stable and makes life that much easier.


The blue bin is the the feeder compartment. This sits on a sliding shelf for easy access. Water comes in via siphon action through the air line tubing from the overflow, and water drains out through the 3/4" hose going into the biofilter.


Here's the inside. Water on one side, sand on the other for the crabs to climb out on. There's only a quart or two of water, so the modest flow from the air line tube provides plenty of turnover.
This is impressive, Dan! Nice little crab habitat, too.

I suppose someday you'll be one of those people who has the tank in the living room and a whole roomful of equipment behind the wall!

Thanks for the kind words, everyone. Paradox, that's exactly how I feel. Finding and implementing the perfect solution through trial and error is just as enjoyable to me as the cephs.

The system is very functional even if its not that attractive. Nancy hit the nail on the head in that some day all of the filters will be in a separate room, and then it will look pretty nice (or as nice as an AGA pine stand can look!).

Also, a new inhabitant is being dripped as we speak! I'll post a thread about him as soon as he's photogenic.

Wow! I am sooooooo envious. Beatifully constructed.

I renovated my 75's filtration today. Nothing nearly as impressive though. Just a new wet/dry that's been sitting unused underneath the girlfriends empty 60 gallon cube. This is my first attempt at DIY plumbing. Not too shabby if I must say myself. Taking my first steps towards a larger Octo. Einy's about to move into his own tank, after being in the critter keeper for almost 2 months. (I know, but size wise it's relatively like a Bimac in a 75 or larger) After that I'm going to order another one.

Got rid of all the HOB stuff! Minus the overflow. I'm using an 800 gph pump, and luckily the skimmer fits on the wet/dry as well. There is a cylinder for a skimmer that was built into it, but the rest of the parts are missing. I'll probably try to build my own to complete it so I can take the other skimmer off. For now I also added the components of the old filter to the wet/dry to seed it.

I have to figure out how I'm going to screen off the hang on overflow with some of that window screen. I was looking for it at Home Depot today, but I came across nylon air filter mesh. It's basically meshed fishing line, thought that would work fine.

Anyway, sorry to intrude on your work of art with my amateur stuff. I'll definitely be eyeballing your setup to improve on mine.
DHyslop;83736 said:
Intrude all you'd like! There's nothing I love more than discussing aquarium plumbing.


PS - Drill it!

Dude, I would LOVE to.

I have the in-tank overflow equipment, minus the actual overflow divider piece. Layla, my girlfriend, has a 60 gallon cube that's already drilled, but the guy she bought it from sealed off the holes with a piece of glass. We have tried and tried to remove the glass, but we only ended up breaking it.

Eventually I want to just trade in all the tanks I own and get something in the 200+ range, reef ready. It will be an in-wall tank, with a room on the other side for all the equipment to be concealed.

Maybe a 1000+ gallon tank for a Dofleini.... hahah yeah right.

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