# DIY 3D Background "Rift Slate"



## sigpi906 (Dec 5, 2013)

This is my first attempt at making a 3D background. I've watched a couple of videos, took a lot of my techniques from the instructables website and of course, did a lot of reading on here here and aquariumadvice.

My background is for a 90 gallon cichlid tank. My designs going in a 48x24x18 tank.. It will measure 42x23x11 with cutouts for the heater and 2 filters. I'm not finished yet, but I thought I'd at least begin documenting my project here and update it when I've made progress.

I'm going for a sharper shale-type layered look as opposed to the smooth river-rock look. I wanted the rocks to resemble the course layered slate-like sedimentary rock that we see around a lot of the lakes here in Arkansas. I started out thinking that I'd build the wall on these back-boards and install the whole thing, but the more I think about it, I believe I'm just going to continue using the backboards as a guide to keep it straight and just install the rocks without the backing boards.

For the build I'm using 1" styro from HD and GE1 Silicon. I made a hot knife out of a 100w soldering gun and some 16 gauge wire. Add in an exacto knife, and that's all I've used so far.


----------



## sigpi906 (Dec 5, 2013)

So my question now isn't so much "how do I proceed" but more like "how would YOU proceed?"

My thought was that I was going to use 2-3 thin coats of mortar mix (dyed dark to get the styro covered and get the rock texture estrablished Once I've got the coverage I need with the mortar mix, I was planning on adding color to it by using Drylok tinted with concrete dye of add the realism of actual rock.

I'm open to opinions on technique and advice on how to proceed.. also any words of caution or advice. We all learn from each other and maybe something I screw up here will help the next guy behind me...


----------



## wreckmster (Oct 29, 2013)

That looks cool. first, I would test fit it in the tank to make sure it didnt come out of square.. Run a heat gun across the whole background to harden the Styrofam prior to coating. this will melt and harden the sytrofoam. do a couple test pieces and you'll see what Im talking about. It adds a nice texture and shapes the design while also giving a solid surface for the Drylok. I wouldnt bother with the mortar as Drylok(to me) feels like thinned mortar and has waterproofing properties. I would just do 4 coats of Drylok. 2 plain, 2 tinted, and a light highlight, drybrushing coat in the cracks and ridges.. Then seal the whole thing with Pond sealer and silicone it in the tank. just be sure to test fit after every coat to make sure it will still fit the tank. Nothing stinks more than getting it all done and the front corner is away from the glass 2"


----------



## tomas2010 (Aug 31, 2013)

Looks great!
I would go for two or three peaces instead of one but thats me.
Are you sure you can fit it in one peace?
As Wreckmster said check if it didnt come out of squere
Heat gun is great idea too.
I cant really add much more
if you go for cement dye I would suggest using them all in same time 
to correct spillage etc.
I was using three different cement dyes and had only one cup
so one colour at the time and as it was watery thing 
it went to the parts I didnt really wanted
so, to correct anything I had to go for new colour
Perhaps that will save you few minutes.
and yes you deffo need pond sealant, it will harden everything.


----------



## iridextr (Feb 8, 2013)

I would just like to say that I LOVE the way you tilted some of the pieces and don't have them all at the same orientation. The one thing I've never found appealing about this style of backgrounds is that they always look unnatural to me. Horizontal stratification is obviously natural in sediments but nature always loves to throw in something that breaks the pattern, especially when the surface is exposed. This is simply great in my opinion. I cannot offer any advice though since I've never done a foam background, but I'm eager to see how this turns out for you!


----------



## sigpi906 (Dec 5, 2013)

Alright, here is an update on my progress.

I built it all together, then separated it into two pieces to paint and to allow it to fit into the tank. I finished up the foam pieces, made cutout contours for my intakes, returns, and heater.

View from the back (I've never seen anyone post this... thought it might be helpful to another DIY'er some day 









I had my Drylok tinted light grey at Home Depot just to knock the bright white out of it. So far I've gotten 3 coats on it. 
1st coat - light grey.
















2nd dark charcoal. 








3rd Mix of charcoal, Buff, and Red to make a muddy red color. (Clearly, this coat was still wet when I took the pic)









I think I'm going to put one more full coat on in tonight before I start adding detail with a destroyed dry brush.


----------



## sigpi906 (Dec 5, 2013)

wreckmster said:


> That looks cool. first, I would test fit it in the tank to make sure it didnt come out of square.. Run a heat gun across the whole background to harden the Styrofam prior to coating. this will melt and harden the sytrofoam. do a couple test pieces and you'll see what Im talking about. It adds a nice texture and shapes the design while also giving a solid surface for the Drylok. I wouldnt bother with the mortar as Drylok(to me) feels like thinned mortar and has waterproofing properties. I would just do 4 coats of Drylok. 2 plain, 2 tinted, and a light highlight, drybrushing coat in the cracks and ridges.. Then seal the whole thing with Pond sealer and silicone it in the tank. just be sure to test fit after every coat to make sure it will still fit the tank. Nothing stinks more than getting it all done and the front corner is away from the glass 2"


Wreckmaster, I wanted to let you know that I wasn't able to truly test-fit it into the aquarium, because the tank it's going in is occupied... but I did carry it in to see if it came out of square. It seems to be square with a slight bow on the long side, but it doesn't seem to be anything that silicon and some bracing while it cures won't fix.

I also took your advice on heating it. I didn't have a heat gun to use, but I did take a blow torch (the kind used for soldering) to go over the whole thing. It did a good job of rounding off some of the stray pieces and making the project a little more cohesive-looking. It also added a nice hard shell to the styro that it didn't have previously. Thanks for that advice. I really think it helped that first coat go on much better.

I need y'all to tell me about this pond sealant. What is it for? I've only seen one or two other posts where people said they were using it... is it a necessary final process or just suggested?


----------



## GTZ (Apr 21, 2010)

I don't have any personal experience using pond sealant but from what I gather, it's an additional layer of protection against fish or plecos that nibble algae. Worst case without it would be the pink foam showing through in spots.


----------



## sigpi906 (Dec 5, 2013)

GTZ said:


> I don't have any personal experience using pond sealant but from what I gather, it's an additional layer of protection against fish or plecos that nibble algae. Worst case without it would be the pink foam showing through in spots.


Yeah, that would NOT be ok with me. ****, :lol: I'd be more likely to get rid of the Plecos than the background :lol:


----------



## Steve C (Oct 9, 2011)

> I need y'all to tell me about this pond sealant. What is it for? I've only seen one or two other posts where people said they were using it... is it a necessary final process or just suggested?


I've done them with and without Pond Armor Pond Sealer. The one I just finished in my 265g tank I sealed, that was the first time I used it and to honest I will probably use it on all my future 3D BG's from now on. It protects against plecos as mention, but it also adds a durable coating to the drylock/background that will probably double the durability & life of the background itself. You will still get a number of years out of it if you don;t use Pond Armor, but if you want the BG to really last a long time 10+ years then Pond Armor will help make that happen.


----------



## sigpi906 (Dec 5, 2013)

Thanks Steve. So if it's a durability issue, what would you say if I told you I might only want this background for a maximum of 2 years? Would you still suggest I spend the $$ and time knowing I'd have to purchase the PS again for the next one? Is it a necessary step for a short term project?


----------



## Steve C (Oct 9, 2011)

If you are only doing 2-3 years then save your money and don't worry about the pond armor. You'll get 2-3 yrs out of it without pond armor no problem.

BTW looks real nice :thumb:


----------



## sigpi906 (Dec 5, 2013)

I got another full coat of Drylok on yesterday afternoon and then started dry brushing to get the texture I wanted. I used a destroyed brush (that I made with a box cutter) to add the texture with different shades of Drylok that I mixed in small batches to the colors I wanted for each layer.

I took some pretty random pictures of the process that I hadn't seen anyone else post just in case they help someone else one day. 
This was after the 3rd coat of drylok dried. This is what the "muddy" color turned out to look like when it dried on top of the charcoal grey. 









Random mix of dryok colors I used to make the texture









"Destroyed" Brush









Highlights on the "worn" parts of the rock. This is also a good angle to see what my cutouts look like for the intakes and returns. I made these by taking a propane torch with a pencil flame and just burning out what I wanted.... I decided on this method after trying (and failing) to cut the shape out with an exacto knife.









Brush used for final 3 coats









Close up of one of my filter return cutouts. The return will sit in front of the background, but still be recessed and out of the way. This should maximize functionality while minimizing visual impact. (the intake cutouts were made the same way and you can see them on the big pictures if you look for them)


















This might give you a good idea of how many dry-brush shades and coats I used. I can see at least 5 in this pic... I did 6 or 7.. not all visible here. It might be overkill, but since there is no substitute for nature, I feel like more is better (in small doses)



























This is what the final product started to look like.


----------



## wreckmster (Oct 29, 2013)

That came out really good. You did a great job. the different color highlight shades really make it look realistic. You are correct that the heat hardens the foam and allows the Drylok to be applied easier. It will be nice to see it in the tank..


----------



## sigpi906 (Dec 5, 2013)

I let the silicon cure for 72 hours and put water in. Let that sit overnight. The water seemed very filmy on top so I did a full water change the next morning and installed fish and decor. Going great so far and the fish are very active, hungry, and happy.


----------



## tcald429 (Dec 27, 2012)

This background and tank turned out great, thanks for sharing.


----------



## Steve C (Oct 9, 2011)

Looks good I like it :thumb:


----------



## BratmanXj (Feb 11, 2013)

I am not artistic and have enlisted the help of my sister-in-law to carve a background. I showed her this article and we've decided to change directions and go this route. Really turned out great.


----------

