My Completed DIY Background

[Donaldm]

A month or so ago I completed my first DIY Background for a tank I was revamping. I did quite a bit of reading up online before starting it so had a fair idea of what I wanted to and had to do.
My tank is 30G and has two braces on the top so I couldn't do one big background so opted for several smaller pieces that I could fit in between the gaps.
I am not creative and have had failed attempts at DIY things before so wasn't entirely sure if it would turn out as I intended.

Unfortunately I never took photos as I was building it as I hadn't signed up here but I've taken some shots of it now and the polystyrene I used to build it.


The materials were :
A few spare sheets of 1 inch thick polystyrene (You can get them at DIY stores as insulation sheets or smaller sheets are used as fish box insulation)
Aquarium Silicone
Portland Cement

The only tools I used were a kitchen knife to cut the sheets and a paintbrush to apply the cement

As I was creating small sections I cut the sheets into shapes, using a straight edge as the back of my rock formation so I could silicone that to the tank sides. I cut several semi circular sort of shapes but sort of waved as I cut it. a bit like this


These are some of the spare bits of sheet so they are not the shapes I used but you can see the thickness and roughness of the edges.


I didn't care about how careful I was cutting it as the concrete will soften/smoothen everything up
I then glued these in layers of 2 or 3 to get a small rock outcrop effect and left the silicone to cure for 24hrs.
I also built a large vertical corner section to hide my heater and overflow and that was just built up using the same sheets layer on layer until I reached the height of my tank. occasionally missing a bit so there were gaps for water flow. The best was I could describe it was like building a 2 sided jenga tower whilst glueing it together.

Once all the silicone had dried, I started painting it with cement. I did about 4 layers in all and each one got slightly thicker consistency. The first was like milk and the last was like thick soup. I just did it on the kitchen floor on newspaper and left it for about a day for each layer to cure. I did add a bit of cement pigment but noticed that the different thicknesses of concrete mix had different hues anyway. My end result is a bit camouflage looking (as you will see)

After it had all dried, several days later, I siliconed the sections into my tank. I used some of the smaller bits on the floor to come up out of the gravel and also cut a couple of flat single sheets at an angle  (like the big bit in the pic above) so they stuck out at that angle from the floor. I left the silicone to cure (again) and then filled the tank to check they were secure.
All OK !

I then did about 7 or 8 refills of my tank over 3 weeks as the concrete leaches into the water and raises the ph. mine was at 10.5 or so for a while before it started coming down. I was getting frustrated after the 3rd or 4th refill and read that baking soda helped. I added some and not sure if it was that or just another few refills but it did eventually stop rising and stay the same as my tap water.
I don't think there is anything you can do to get around this. It takes time and multiple refills of the tank.

I put a few 'test' fish in after that and since then everything has been fine with no concerns over water quality. Tests are spot on and fish are healthy.

So unfortunately no in-build photo's but here's the completed tank. The few plants are poor specimens from fleabay and I'm glad my own sword plant has started sending out runners that I am growing on and are much healthier than these so I won't need to buy again.

The Completed Tank


The heater and overflow part on the left (Jenga Tower) with pieces on the floor and back wall




Floor and lower back section


The back, looking down


The back, looking up


The sloping pieces (although taken from wrong angle as they are sloping towards you)


I've probably missed loads out but what I hope what I've said makes sense. Overall it came out a lot better than I had hoped. The tank back is black so I think the outcrops do really seem to stick out, but don't take up much space and I really like the sloping pieces.

I did take a while but was several small tasks with waiting in between, so did need some patience.

[TropicalFishForums]

[Coin]

Looks good, impressive for a first attempt