Making Diy Styrofoam Background (update-more Pictures)

[Scott MacAdam]

Yeah, i agree, making a mould first may have been quite helpful, and also i strongly reccomend placing some weights (such as the marble mentioned by the post above) this would have helped mine out a bit, when i make a large one i will denfenatley do that to make sure it stays down, but for this project, it seems to sit in there quite nicley and is held down by a bit of pressure from the lid , not quite how i invisioned it but the fish love it and to take it out now and start makeing changes to a problem that fixed itself dosen't seem necesary.

 

[RRasco]

a few things...

1. adding salt during the curing stages is supposed to help cure the concrete stronger. i have heard from some places it helps to leech out the lime which causes a dramatic rise in pH. this lime leeches out over time and is not toxic, just alters the pH to the unlikeness of the fish. although i have researched it and found that they have done studies on bridges and that the supports that are under water(salt) are stronger than those that are not. when i did mine i used water softener salt from lowes. it was $4 for a 40lb bag. i added about 5-10 lbs per cycle of the tank. i filled then drained 3 times with salt and am currently rinsing in freshwater a few cycles.

2. it is easiest to silicone it to the back. i am almost positive that mine would have stayed under by itself, but i wanted to make sure it did, so i gobbed on some silicone and stuck it in. worked like a charm and is now 1 with the tank.

3. you could use an epoxy but this is a dramatic rise in cost of this DIY.

you can see my diy bg i did for my 20 gallon wide. it was also a test piece before i did the 55 gallon.

http/www.fishforums.net/index.php?showtopic=161891

 

[Scott MacAdam]

yeah , I must say, mine likes to float, given the chance. when I make another for a larger tank, I will use less styrofoam, more cement, and maybe even cut some holes in the styrofoam and fill it with some rocks and seal it all up just to make sure. My background is really small (for a 10gal) so it dosen't really matter, it is now held down by a cross-section for my lid.