Fake Rocks

[jeepjon]

Alright...so I have this 5.5 gallon sitting around doing nothing, with a light setup and everything. I even have some LR to play with (a few extra pieces laying around my larger tank. SOOOOO....I wanted to set it up, but I wanted to make a few fake rocks or a fake back/side ground that would add to the dimensional feel of the fake reef. What could I use? Fiberglass and resin mixed with aragonite? What about some kind of plaster material? I want to avoid the whole fake live rock procedure with aragonite, CC, and concrete, because it seems pretty involved. If I could get away with using the fiberglass and aragonite sand mixed into some resin on top of it, I would like to use that. Would that hurt the saltwater, would it leach? Sorry for the long question, but I've got this itching to tinker...and it has to be met.

EDITED:::: how did my title get so screwed up to begin with????

[yardboy]

Personally, having made live rock from cement and worked with fiberglass on my boat, I'd go with the cement every time. Yes, the cement has to be cured, if it's a big enough piece, but I'd dare say any resin you used would have to cure too.

I wonder if you could get away with cycling the tank and rock at the same time with the cement rock? I'll have to try that!
Is that what the "DIY bug" is, when you have something "just laying around" and can't stand to see it being idle?!

[jeepjon]

I was thinking more along the lines of making rocks that attached to the side and back glass, kind of like making the walls of the tank more along the lines of a reef cavern than just tank glass...I thought it might be neat to have a reef in the center of the tank, but with the tank walls looking like rocks coming out of the walls....It's hard to describe what I mean exactly... ...I was thinking of actually coating some kind of styrofoam (don't know what would work) with concrete, so I could shape and glue the styrofoam to the walls, and coat it with concrete/mortar to look like reef rocks...would that work? I'm just new to this kind of work, you know?

[jeepjon]

and yes, I just hate seeing that cool little tank and imagining all of the interesting possibilities that could abound!

[jeepjon]

OH, what I meant by curing wasn't the actual hardening/curing time...but the time when the lime leaches out of the concrete...I thought maybe once fiberglass was cured, it wouldn't leach into the tank at all.

[wharyat]

Isn't fiberglass non-reactive?

[jeepjon]

I thought it was...but I wasn't 10% sure. For what I wanted to do, I thought fiberglass would be a good choice. I may or may not be right....but I'll find out at some point!

[yardboy]

Here's a thread from ths months TOTM at RC, he did just what you are contemplating: http://reefkeeping.com/issues/2005-02/totm/index.htm

I would consider fiberglas non-reactive also, after it cures, and I don't know how long that would be. I'm sure you could find out somewhere. Heck, epoxy is a type of resin used to make fiberglass.

[wanareef]

Mixed corretly - it will cure in 24hrs I've built ply tanks before using epoxy as the "liner" for the plywwood. Gotta work with the stuff in a well ventalitated area.

[jeepjon]

I was thinking of using fiberglass over foam or acrylic of some sorts to make an overflow box for my powerfilter and a nice cave/overhang/arch that could be coated to look like LR, and then seeded with real LR....I think I'm going to do some major planning and start work this weekend.

[orlenz]

anothe option would be to use agrecrete, you would need to make a form that is the same size as your tank, then you could make one large rock that would slip in your tank, and cover the back and sides, you can make it with with caves shelves, even an overflow, whatever you want, the stuff is not the easiest to work with but if you use rubber gloves, ballons, crushed coral, to support your shelves, cabes, while it dries it would work, fiberglass rocks would look good but do nothing, with agregcrete it would be functional as well.

[jeepjon]

Well, I used some carved out foam that you use to put silk flowers in...and i made some nice arches that would look good with real LR added into the tank. I now need to know how to coat them...does anybody know of any paint that is safe to have in an aquarium once it is dry? I am thinking I'm going to try to paint it or at least just coat it with mortar...I'm not sure what would happen if any of the foam was exposed....do you think that it would hurt the tank to have foam exposed in the tank once it is set up and running?

[Geoff]

ok, i am sick of playing with LR. i just can not get it the way i want it. not making it look good, i am ok with that, it is the getting it functional that is really difficult. has anybody found a place i can get very large chucks of aragonite? i am thinking of carving my own pieces. i figure if i start with some 2 foot cubed chucks of this stuff i should be able to create the tank i want.

G~

[RobinsonFam1]

on rc there are alot of threads about making a back drop or rock wall using foam. i even read one that was based on using "Great Stuff". the expanding foam in a can. while its wet sprinkle sand on it and thats basically it. some say it wont last. others say that they have been using the same stuff for 20 years in commercial tanks with no problems.

heck i might even try it in a tank that i have laying in the garage!?

i never have worked with epoxy like the way you mention. if it works for ya let us all know!

[jeepjon]

Well...The epoxy is still sticky....it needs more curing time...but the problem is that it is clear, and shows the green dry foam underneath. So...I'm going to try to mix up some concrete/mortar and coat the foam with it. What I'm building isn't the full reef structure, just some wall stuff and an arch....so I'll be able to add in some LR to make the bio filter functional. I hate trying to work with LR to make interesting aquascapes, which is why I'm looking into alternatives. I figure try it on small tanks now, so that I can use it on large tanks later....What about buying dry old LR (have no idea where to get it....maybe even use old lava rock for gardens???) , and cutting, grinding, and drilling it together and using silicone to put it together, and then seeding it with regular LR?