Building a DIY Background – Continued

So now everything has sat overnight and all cured! Time to play with concrete!!!
OK don’t mix the whole bag at once!! You won’t use it all for the first coat. The 60Lbs bag of mix got me through 3 solid coats and a wetwash easily.
Now for my look I was going for red rock color that I think would look great with the black sand substrate I’m going to be using. There are 4 colors to pick from for the cement. Charcoal, Buff, Red, and brown.

My mix in a 5 gallon bucket: (I did this for the most part for each of the 3 coats)

  • 10 pounds of cement mix (depending on the look you want you can either use the mix as is or sift it to remove the gravel.)
  • 1 cup of fortifier
  • 2-4 cups of water (depends on consistency and look you want. you want it a bit soupier then a normal cement mix but not so soupy it’s water. Almost like a paste) Hint: add water 1 cup at a time and mix
  • 1/8 – 1/4 cup of coloring (add this slowly as well… gets real dark real quick if you add to much)

I also cut a the bristles of the paintbrush in half to make it a little firmer to use

For the first coat I went with leaving the gravel in the mix the dark charcoal coloring. This will help accent the background when you apply the lighter coats onto it later and I think the gravel gave it a nice natural look. Basically, I just started scooping out cement on the brush and started “painting”. Again, depending on how you plan to to stick this to the tank, be sure to keep that surface cement free. Be sure to get everywhere with a good coat all the way around.

Once you’re done let it sit over night. Something to consider… The fortifier said it eliminates the need to water this down during curing “in most cases”. However that is also for much thicker layers of cement of 2 inches or more. This will be a 1/4 inch if you’re lucky. So just to be cautious, I did take a spray bottle and water this down every couple hours. Up to you if you do that or not but in my opinion it‘s worth the 5 minutes of my time.


For the second layer of this I sifted out the gravel. I figured I had enough “rock like” look. Again up to you. I also went with a darker red layer this time and mixed it well. Then I added a small amount of black and did not mix that well at all. I just sort of swirled it. Doing this will add streaks of color to the background.


For the final coat I again sifted out the gravel, and this time went with a much lighter red color. This I mixed up fairly well. You could still some of the grey of the cement mix. Again looking for a streaking color to add a bit of depth and a natural look. I also made this layer just a bit soupier then the other coats. (extra ½ cup or so of water) Also instead of brushing the cement on, I dabbed at the background. This got rid of the brush lines and gave back a more stone, stuccoed look. Also because some areas were a bit thinner then others you could still see some of the darker spots from the previous layers. And again I let it set over night with the here and there water down.


So at the end of this I had about 5 pounds of sifted mix left… I was going to toss it but decided to use it for a sort of wetwash or drydrush effect at the suggestion of an artist friend of mine. For this mix I used just about the same amount of water as I did for the 10 pound mix. Very soupy!
I also again used the red and again mixed it so-so. I also applied it a bit different. I dabbed again through the whole background but before I did I knocked off most of the watery cement from the brush. So when I dabbed the background barely anything was actually sticking. All this basically did was add some highlights to some of the rougher spots and corners. In hind sight a slightly darker color might have been the better choice but I am still happy with the overall look.


The pictures here really don’t give it justice. The highlights don’t show up that well… They are really there though! lol I hope the pictures of this actually in the tank and wet will show this a little better.

So now you are done with the cement. I let this sit for a few days before really doing anything else to it other then watering the hell out of it every few hours.

These next couple things I did are optional and for the most part are just “clean up” type things.

Concrete doesn’t really stick to plexiglass (which I knew and expected) and just moving this around here and here for pictures and just through curing I noticed the crete was cracking and coming loose on the plexiglass. I pretty much figured it was just a matter of time before it crumbled off and I would rather see that now then when it’s in my tank. I really don’t want my soon to be new Bristle nose chewing concrete… So I figured I would help it along. With the handle end of a small screwdriver I tapped along the concrete on the plexiglass and broke most of it free right up to the spray foam. I did this all the way around the background and through the caves. I did a bit of scraping along this new edge with my screwdriver to make sure nothing was loose and to clean up that edge a bit. All this took me maybe 30 minutes.


When I was done cleaning I didn’t really like the sharp edges I now had. So I thought the simplest of solutions was to put a couple nice sized beads of silicone around the edges. I’m not overly concerned with the look of the base since I plan to have the sand substrate well over this point. This was more concern for my soon to be new friends. I know some of these guys like to dig and figured they would get cut up if they ran into that sharp edge. Being a newb to fish care I’m sure I’m being over paranoid but that’s ok. Besides I have soo much of this stuff left over from redoing windows its not even funny. Even with as nuts as I’ve gone with this stuff I still only went through two tubes.



So still having a bit of silicone left in the tube, and now thinking of sharp edges, I decided to place a nice bead around the edge of back wall of the background. I figured this would give me a nice rubber bumper to protect my glass.


And that’s about it. We’re done!! So grab a drink to celebrate and show off your insane creative skills. Re-acquaint yourself with the family and let this cure a couple days.

Hint: After playing with the silicone (if you have) you understand how much this stuff sinks. Go kiss some serious butt… buy some flowers… go out to dinner because this next part of siliconing the background is going to stink out the room your tank is in for a couple days. Also plan on some butt-kissing while the living room stinks of vinegar…


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