Refurbishing journey of a 70 gallon 1/2 circle tank

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Aquarium Advice Newbie
Feb 28, 2023
Hi there,

I’ve posted previously and alluded to a major tank refurbish and overhaul, and though I’m decent at diy, and researching, I’m also not an expert in anything tank related. But I have decided to tackle my tank from a slightly different (not easier or less time consuming, necessarily) slant than other diy tankers, so I figured I’d post in case anyone else decides that they don’t want to do things the easy way ��

First: I have a gorgeous, initially very expensive (over 1k) half circle oceana brand tank which seems to be very rare, and isn’t findable any more. I love it because it sits flush against a wall, and takes up less space than a square tank.
BUT, the design was likely for primarily salt water, I think, so it has a bulkhead in The center of the tank which then leads to pipes and a sump in the cabinet below the tank. Also, the tank is as high as it is wide, almost, so it is a very tall tank, which makes it really awkward looking for small freshwater fish, as they get lost in the depth of it. We decided a long time ago not to mess around with salt, as we aren’t really set up for it, and don’t have a good area in our house to mix water, etc… so after realizing initially that tiny fish weren’t ideal, I went with cichlids and a fairly stark background, mainly to attempt to hide the bulkhead, and it’s been a cichlid tank for 20 years, happily.
But covid hit, and for 3 years I neglected to return my larger cichlids in the spring and start again with younger ones, so a couple got big and mostly killed off the others over time. So by this year, it’s been looking sad and tired, and I’ve kind of been ignoring it, since there hasn’t been much new to look at in it for a long while. So I figured since we have barely any fish for the first time in 20 years, maybe it’s time for a re-do.

I started looking at aquascapes and planted tanks, and figured maybe I could 3d print a landscape that would a) be hollow, b) hide the bulkhead still, and c) allow me to have smaller fish, while still having interesting eye catching scenery for the depth of the tank, and have a large enough “landscape” that the smaller fish don’t just use the bottom 1/4 of the tank.
Some of my challenges are: I live in prairie canada, dead of winter, and there is no good free interesting rocks or driftwood to be found. It’s tragic. I paid an insane amount of money for red lava rocks initially to occupy the tank- the silly things for for like, 20$ for ONE rock at the darned pet store. And it takes a large number of ricks to hide the bulkhead of this tank. And building up on this tank is essential. I don’t like the instability of Rocks, and I didn’t like that they were insanely hard to clean when they got algae, and overall, it isn’t my ideal medium. A fake landscape seemed like a better alternative, but I wanted something more stylized than the foam/sand builds out there,. I don’t like the concrete look and didn’t want something that leaches ph constantly for a while, I’d prefer inert, and I’d prefer it to be hollow, and ideally not attached to the tank permanently.

So I decided to tackle all those problems by designing and 3d printing a background, then post processing it to give it texture/color.

It’s been a bit of a journey so far, I’ll try to post pics in order, I’m not sure if posting order stays the same or changes,- hopefully these will end up in order… I’m not done yet, I keep finding new issues to tackle, but it’s coming along :).

The pics below were the current state of my tank, which at this point kind of looks “meh”…. IMO.


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]I first started researching and falling down the black hole of aquascapes. This stuff wasn’t there 21 years ago when I got the tank initially. Super gorgeous potential, and some really neat builds. First issue, I tended to prefer the tank builds that have the eye drawn to the hole in the center of the tank- and that is pretty much opposite of this tank- I’ll end up needing a “volcano” look, since the intent is to hide the bulkhead. But I wanted something that was at least offset, or visually interesting from multiple angles. I posted some of my “research pics” here in Imgur.
Once I got the general idea of what I was looking to print (I got a 3d printer this year, and it seemed like a neat thing to try- and something that hasn’t really been done, likely because it’s almost too large scale overall, plus the software for 3 d building is not for the faint of heart).

Anyway, I am NOT at all knowledgeable in 3d software. I have dabbled with tinker cad, and mesh mixer, both which weren’t quite what I needed to create something from scratch of this size. I downloaded and took a bunch of time to work and learn blender a bit (huge free software, not for the faint of heart). I hit a knowledge wall there, and imported it to mesh mixer to finish it off, hollow it out ( this took me a week to figure out how to do), and chop it into sections to print. This link shows what I built in blender, (sized to match the tank/ bulkhead), and the part printing process.
I glued each section together with crazy glue, instacuring it with baking Soda. Which did the trick perfectly.
I also decided that since it was hollow, I was going to attempt to make a couple of sand waterfalls in the build- knowing that it was likely going to require some post processing without having built it in advance, but I had faith I could do that…
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