3d Background Sealant Choices

Hey all,

Just wanted to ask any of you that have built your own foam 3D backgrounds for your aquariums what you used as a sealant over your cement coating. I've found a few different products (all of which are quite pricey) and don't want to waste money on the wrong thing. Any suggestions?

Thanks,
Bryan

 

in my research and sparse experiments ive noticed you don't HAVE to put a seal on it simply let it soak for a few weeks changing the water every day it will steadily get less foggy till all of the minerals leach out.
my question to you is have u ever used mortar instead of cement and what were your experiences?

 

The background I made has some intricate detail and so I've been coating it in thin layers of cement. This is the first one I've done so I don't have experience with mortar. I originally was planning to not seal it and just let it equalize in the tank but since the cement is so thin, I've noticed it cracks easily and I'm worried that after time it may just dissolve off in spots so I wanted to coat it with something that will make it more solid. The epoxys I've found seem to run between $100-$200 for enough to coat the flont side of the background.

Here's what I have so far.

 

first of all props on your design very clean looks professional . To keep it from cracking best thing I have found it misting your project as it cures it will allow it to dry more evenly and less cracks to form, another coat never hurts your essentially just adding another layer of rock onto it, in the thin spots just give it a little extra attention u don't want to thin a layer anywhere or just like u said over time it may show through depending on the situation. also gives u more weight on the background less chance of floating or separating from the tank (minimal but still). as well as more opportunity to tweak your colors textures and other such details.
I have made a few small underwater waterfalls for friends and family and have never used a special coat and all their fish have lived happy lives no problems, ill simply soak it in a 5 gallon bucket or a 20 gallon tote (after its completely cured of course)depending on the size for about 2 weeks until the water is crystal clear and no more leaching
yeah when your looking at the price tag of some of those sealants they can be very proud of their product I don't feel its necessary unless u have money to blow and don't mind
another thing about some of those sealants I have read several of other ppls diy projects blogs and a handful of them had issues with the sealants bleeding through the cement and eating away at the styrofoam like an acid and leaving hollow spots which caved in or left air pockets not sure how. But I noticed it only happened to the ones that attempted some kind of sealant. Not all of them only some
Didnt mean to write u a book sry bout that.

 

Try pond armor; it's a 2-part epoxy and easy to use. It's not as expensive (but still a bit pricey...about $65 for smallest size) but it's a good product.

You definelty don't want cement in the tank unless it is sealed. They'll leech on top of cracking.

 

ive had an underwater waterfall in my parents tank for close to 2 years now and it wasn't sealed still holding up no cracks I put 5 coats of a medium thickness mixture let cure about a day in between coats while misting and and than soaked for 2 weeks her parameters stay perfect other than routine maintenance.

 

tigerfish420 As far as people's sealants dissolving their foam, I've seen those videos as well and was the main reason I didn't want to use any sealant on it. I don't have the fish in the tank yet and was planning to soak the background in the tank with 50% daily water changes until the tank is clear and the ph balances back out. So far I've done 3 coats on it so I could just continue to build up thin layers on the front. The chipping is occurring when I accidently press on the cement when I'm moving it or if I bump it on something, not during the curing process. Also, the skull in the lower right of the background is an underwater water fall.

KinsKicks I looked at the Pond Armor as well and with the size of the background I would need 2-3 sets to cover the whole thing. So like I was saying, it would run $120-$180. I may have to go that route if I can't get the cement to hold up once it's exposed to the water. I was hoping there was a cheaper sealant option out there but it's not looking like it.

 

I would suggest taking a few smaller pieces of styrofoam and trying different consistencies of cement. could see if more or less water would affect strength, I did something similar when adjusting color and texture, my pieces have been smaller so I wasn't having that specific issue.
Could you spot treat in the tank?
It looks like a bigger piece, if your moving it by yourself have a buddy help, more contact points means less stress on those points. also make sure when u silicone it to the tank lay the tank on its back you won't have to press so much to make sure you get a good seal.
Underwater waterfalls are amazing I love the illusion it gives some of my uncles fish actually dance around in the falling sand, I made one with a separate tunnel leading to behind the waterfall so they can swim through in and out they love it. (very difficult to paint the inside of an 8 inch curved tunnel only 2 inches wide and know you got a solid coat lol)