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Sat Feb 09, 2008 11:20 am

Looking good! What did your research into to the rock type of these structures turn up? I wish there was a good geological map of the rift lakes area - now that would be a great resource.

Sat Feb 09, 2008 1:15 pm

Thanks for the compliments. :)

jcollette3 wrote:Looking good! What did your research into to the rock type of these structures turn up? I wish there was a good geological map of the rift lakes area - now that would be a great resource.

After many frustrating hours of surfing I couldn't find anything difinetive. As you had pointed out Mara point is in an area of origeny and could possibly be of sedimentary/metamorphic make-up. Right now I'm leaning towards painting it to look like gniess useing this picture as a guide. http://www.foxislandalliance.org/brochu ... ock19c.jpg The colors may change but the application will be similar.

Another interesting pic I found is from Australia. The appearance is very much like the formations at Mara point. http://farm1.static.flickr.com/63/17357 ... 81.jpg?v=0 I'm still kind of undecided whether to paint the base of the formations to look like sedimentary rock with "pebbles" coming up out of it or just going with the gniess look.

Sat Feb 09, 2008 2:56 pm

looking great. The first link "rock19c.jpg" looks like the same color as the granite in my 45g

Sat Feb 09, 2008 5:45 pm

That's some nice gneiss in the first pic! Ha - sorry, bad geology pun! That color scheme will look fantastic. What will you use for paint/pigment?

Sun Feb 10, 2008 1:20 am

I plan to use Sika top seal 107 that uses a polymer liquid for mixing. Colors can be added to it well. I've found a couple of places here in Sin City that carry it but none of them are opened on the weekends and I've been real busy putting in long days at work during the week. If the cost is too much I may just use regular cement and coloring with a little water added.

The first coat will cover all the structures in black. It's hard to see in the posted pics but all the formations have vertical striations worked into them with a small soft bristled wisk brush. As I add dots of different size and colors verticaly up and down the structures I'm expecting that the black within the surface scratches will give it a layered look much like metamorphic rock in which the crytaline strutures were rapidly cooled and not as fully formed as you would find in something like granite.

Sun Feb 10, 2008 10:48 am

Can't wait to see it finished! You'll certainly have some happy fish.

Fri Feb 15, 2008 4:42 pm


Fri Feb 15, 2008 10:35 pm

Im really looking forward to seeing this finished.

I love going down into underground caves and it reminds me of some of the rock formations you see in them.

Good work.

Fri Apr 25, 2008 12:20 pm

Hi Iceblue,
Thanks for a great idea, although mine will be on a much smalley scale!

iceblue wrote:The biggest problem with concrete/mortar backgrounds is the leaching of minerals that raises your hardness to very high levels. I'm hoping to avoid this by having a very long curing time before adding water. Once I do add the water I will also be doing a very long fishless cycle....

I am on a bit of a timeframe though, as the poor fish I have stuck in a crowded tank need to get some space ASAP :fish:

Is there a sealer available, or a lighter mix (maybe a plaster) you could recommend to be safe fairly soon after drying?

Fri Apr 25, 2008 2:52 pm

Plasters are pretty heavy as they get thicker. If you look at the stickys posted at the top of the DIY discussion forum you'll see one for backgrounds. Most of them use styrofoam to make up the bulk of thier structures and use a thin layer of mortar/plaster to add detail.

I made mine with the lightwieght concrete mix to avoid having to go through histronics to keep the structures from trying to float to the top of the tank. It also allowed me to design a lot of caves into the background which imo becomes more difficult when using styrofoam. Down the line sometime I will have to recoat my tank and these structures are easily removed without having to scrape silicone off the tank. The recipe for my concrete mix is at the begining of this thread.

So far as a sealer I believe that Lomax used clear fiberglass resin to cover the structures for his diy 600g tank but was dissapointed by how it changed the colors of his background. If your not keeping soft water cichlids it shouldn't be to much of a problem as the background will eventually seal itself with algae and bacteria. This is my plan anyhow. While doing my fishless cycle I'll also be running my light system to encourage algae growth.

You could also go ahead and make the background and cure it outside the tank. This will allow you to get your fish into thier new home untill the cure is done. Then it's just a simple matter of temperarily housing the fish in another tank or bucket while you put the background back in the tank.

Sun May 18, 2008 8:19 pm

Done.......finally. The next time I build one of these it will be on a much smaller scale. :lol:
I'll start out with a list of the materials I used and then explain how they were utilized with each pictured step.

1 gallon SikaLatexR. This is an excellant concrete bonding adhesive and acrylic fortifier.
1 bag each grey and white thinset mortar. (silicate dust warning)
Quikcrete concrete color. Charcoal, brown, terra cotta, and buff.
Disposable 3" brushes.
Various size cheap round artists brushes.
Water spray bottle.

The first step was covering the whole project in black(charcoal). This took 2 coats using the charcoal color and acrlic fortifier mixed with grey thinset. I first mixed all the ingredients to get the consistancy of liquidy paste. Here, as in all other color steps afterwards, I allowed the mix to sit for a few minutes to get a false set. It will thicken up and seem like it's setting but if you give it a swirl with a stick it'll loosen up. At this point, if need be, I added water from the spray bottle to get the consistency I wanted for application. It should also be noted that the concrete color has a saturation point. Adding more color will neither make it darker nor more intense. Just make sure to use enough to reach that saturation point and use carefully measured amounts when mixing colors together.
For this first overall coat I used a consistency of slightly wetter then melted ice cream...... or maybe more like transmission fluid. :roll:
For the second step I used the white thinset with just the acrylic fortifier. This was applied with the disposable brushes that I modified with scissors to make gaps between the bristles. As the stripes were being painted on and the brush was running out of paint I "dry" brushed the areas in between the stripes.
For the next step and all others afterwards I used only grey thinset for mixing. Here I used the brown, terra cotta, and buff concrte colors to cover the white "stripes" and make sectioned areas leaving black and white dry brushed areas to seperate the colors.....Was not real happy with the results here, but more about that later.
Here is where I started useing the artists brushes. I applied dots of color ( with apoligies to Seurat) mixing the terra cotta with brown and the buff with brown in various proportions. While doing this I desperatly tried to cover the intensity of the picture above.
More dots of color but this time using brown mixed with charcoal in a couple of different proportions. By this time I was pulling hair trying to tone this thing down. :lol:
I finally decided by this point to make a glaze of black and brown to darken the whole thing even further. This was a very liquidy application but it did give me the final look I was wanted. Both to the left and right of this picture are what the stuctures looked like before the application of the glaze...............This was a leap of faith for me.
Close-up of the final product. I sprayed it with water to see how it would look underwater. 8) So, so happy. :) 8)
I can't wait for my fishies to be dancing under the moonlight. :thumb:

Sun May 18, 2008 8:28 pm

Looks sweet! Congrats on an great looking tank. I'm sure it was a lot of hard work, but the results are worth it.

Sun May 18, 2008 9:47 pm

Great job on the caves. Looks amazing.

Mon May 19, 2008 8:51 am

Bentcountershaft wrote:

Looks sweet! Congrats on an great looking tank. I'm sure it was a lot of hard work, but the results are worth it.

I got a crick in my neck reaching in to make and paint this thing but yeah it was worth it. :)

Chefkieth wrote:

Great job on the caves. Looks amazing.

Thanks. Thier are a total 0f 40 caves with 52 entrances. Thier different sizes and configurations so thier should be something for everybody when I finally stock it.
By the way, hows the river tank doing?

Mon May 19, 2008 10:00 am

awesome!! :lol:
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