help with a divider please!

gilsonal · #1 10-09-2009, 11:36 PM

I'm using Great Stuff and covering it with silicone to make a divider between the wet and dry portions of my tank. Unfortunately, I'm having a heck of a time covering it in silicone. Now that I've cut the GS to the right size, little pieces keep shedding off and the silicone isnt sticking nicely. Is this typical? I'm already out of silicone!

Also, is there some kind of silicone I can use that people know is non-toxic that I can get at a regular hardware store? I bought aquarium type but I"m out of that and would like to finish this step by the end of the weekend. Is the GE stuff known to be safe or is that just anecdotal? People seem to disagree.

Lastly, is it possible to build a decent divider using natural stones and siliconing them together without ending up with super murky water? I'm almost ready to scrap the work I did with GS and start from scratch.

stimpy · #2 10-10-2009, 12:53 AM

Hi ! Welcome to the forum. I recently joined myself. I did a lot of research before I started my vivarium.There are lots of "sticky threads" look for advice in one of the many posted threads.The reason you are having trouble with the silicone not sticking is because you need to rough up the GS foam with a coarse sand paper. If you try t just apply silicone to the great stuff when it is smooth and shiney,it WILL NOT stick. Good luck to you and post some pix if you have them.

gilsonal · #3 10-10-2009, 06:28 AM

Quote:

Originally Posted by stimpy

Hi ! Welcome to the forum. I recently joined myself. I did a lot of research before I started my vivarium.There are lots of "sticky threads" look for advice in one of the many posted threads.The reason you are having trouble with the silicone not sticking is because you need to rough up the GS foam with a coarse sand paper. If you try t just apply silicone to the great stuff when it is smooth and shiney,it WILL NOT stick. Good luck to you and post some pix if you have them.

I think I looked in them, and didn't see anything applicable to my problem of crumbling off bits...all the surfaces are roughed up since I carved the foam down, so that at least isn't a concern, thank goodness!

stimpy · #4 10-10-2009, 09:44 AM

Hmmmm, hard to say then.Usually if you go to the top of the forum page on the right and click on search you can find just about any topic.As far as the kind of silicone you use, it depends mainly on what you are keeping in your vivarium.If you are keeping either fish or reptiles,frogs etc,then it must be free of certain additives like mold control.Most people use the GE silicone.Also to answer your last question,yes you could use natural stone,however you would be limited to size, as it wouls weigh a ton! I used natural slate for my waterfall and complete,it weighs 32 pounds. I built in in three pieces,so if I need to remove it I can.Hope that helps.Lastly there are a lot of really experienced people on this forum, I am certain some of them will have some suggestions for you.

beckdg · #5 10-10-2009, 03:21 PM

ge 1 or 2 should be fine. i hear windows and doors is the kind to use but i didn't even check that myself. as for the mold inhibitors they rarely leach to anything insurmountable volume wise when they're underwater imo. giving it some time to "cycle" once you're finished construction should be more than enough to keep harmful chemicals at bay with either ge silicone. biggest thing to check is to make sure it's 100% silicone!

your problem with sticking doesn't seem to be normal. also you say little pieces are breaking off. i'm thinking immediately the problem is debris. do you have an air compressor? if not get a decent vacuum, q-tips and a dry/damp cloth. use the cloth/q-tips to wipe away the debris as best as possible getting the nooks and crannies pretty good. afterward do a good vacuum on your pieces to get them debris free. that or the air compressor should help tremendously. you could also get compressed air in a can (computer air duster) if you don't have a compressor but use it sparingly... it runs out quick.

you could use rocks too but i fear getting a water tight seal would be a pain in the arse with that too. of course it's up to you if that's what you want to do. it would be interesting and a somewhat new approach.

one thing i'm thinking is why'd you cut up the g/s? i would think that sealing that back together would be much more difficult than just spraying a line down and covering it... you could silicone over it and add rocks to that too.

gilsonal · #6 10-10-2009, 03:27 PM

Quote:

Originally Posted by beckdg

one thing i'm thinking is why'd you cut up the g/s? i would think that sealing that back together would be much more difficult than just spraying a line down and covering it... you could silicone over it and add rocks to that too.

I cut up the foam to shave it down to the right size, since it expanded more than was needed. It is all one piece, but the current outer surface used to be on the inside, if you get what I mean. Instead of the shiny smooth surface, its the inside foam, which seems a bit crumbly. Perhaps I didn't wait long enough for it to finish curing?

beckdg · #7 10-10-2009, 03:39 PM

did you use the big gap filler?

i would get another can and start over. this time lay it thinner. do a practice run on a piece of cardboard/paper/wax paper to get a feel for how it expands.

i would think the inside would cure better if it were exposed.

you can also put on some disposable rubber gloves and form it with your hands once it's skinned over... before it's done curing. that should help if you happen to spray a little too much.

don't worry about using different materials i would think. i'm thinking you'd have to start learning all over again. if the next material fails it'd be discouraging and that's not the point of the hobby. we want it to be fun. granted there's hurdles but enjoyment and pets are the purposes.

if you can blow out the loose stuff from the inside and uncover something a little more sturdy try it... if it seems resistance is futile don't fight it.

Twistedsins · #8 10-12-2009, 05:51 PM

i saved myself all that hassle and just made a divider out of a 6" tall piece of plexi glass then siliconed some slate to it..the problem with GS is that it WILL FLOAT causing a not very water tight barrier

froggsong · #9 10-12-2009, 06:28 PM

The GS will be water tight... at least for a long time. If it is sprayed to the glass it can't float. That's why they make one to use in ponds.

beckdg · #10 10-12-2009, 06:54 PM

careful with the plexi and silicone. they don't stick to each other so well. as a barrier it should work well though.