DIY Frag Disks

[whatcaneyedo]

I dont have a lot of extra disposable income but I do have a lot of time so the other day I did some online reading and decided to make my own frag disks.

Materials and equipment:
shallow rubbermaid tub
fine coral sand
type 10 portland cement
water
measuring cup
plastic mixing container
wood stir stick
PVC cement container (used to make mold)

I already had a lot of extra sand from a deep sand bed that I removed from my system so that was no problem. The cement I bought at Home Depot for $12 for a 40kg bag.

My formula as 4:1 sand to portland cement with enough water to make the mixture soupy and easy to pore. 1 cup of cement and 4 cups of sand made about 40 disks.



I used this container to make my molds.



I wet the sand in the tub so that it would hold its shape better before creating the impressions.



After poring I left these to set for 2 days.



The disks are out and are rinsed off. The next step is to let them cure in the back of a toilet tank or some other area of frequently replenishing fresh water for about 6 weeks.



Heres a closeup.

[hillegom]

Just like assembly line cookies.
Good thinking

[ALBERTA REEF]

Nice Idea! I would have to try it some time.

[PoonTang]

Hey, awesome job, I love DIY projects.

[kbd635]

Hey! Can I borrow one or 2, so when I'm doing my MMLR, I can make some "sockets" in it to fit your frags?
K

[whatcaneyedo]

I'll mostly be using these disks to mount soft corals in my grow-out frag tank (I like to suspend my SPS) and they seem rough enough on the bottom that epoxy should work well with them. I've had a lot of trouble trying to get the store bought ones I've used to cement to anything because they are so smooth all the way around. If you're making your own liverock use the top of a PVC cement container to make the exact same impressions. However I wouldnt recommend it... your rock will look like the surface of the moon if you put craters in it like that.

[whatcaneyedo]

I tried making some small frag disks this time. For a mold I used a $9 plastic door mat from Canadian Tire with 1" holes which made over 200 disks at once. They dont have the little pegs in the bottom like the store bought ones do but I dont use egg crate anyways.

I used 4:1 sand to portland cement again and I noticed that the disks are a little more brittle. They are still relatively strong but I am able to snap them in half with my figures although it does take considerable effort. So for future reference 3:1 might be the way to go for these smaller types.

Underneath the mat I had an old sheet of glass because I was worried about the cement sticking down. Peeling everything up was pretty easy and then all I had to do was pop each disk out of the holes with my figures. Now like the other disks I need to cure these in fresh water for about 6 weeks before I can use them.

[cuz]

nice work!! little mass production!!

[zum14]

So how important do you think the media is for the disks? I dont really have any extra coral sand kicking around. I have lots of sand I use in my freshwater tanks but not sure if this will work. It doesnt change PH in the freshwater tanks but they also wouldnt look like coral sand pucks. Any thoughts?

[whatcaneyedo]

I don't think its critical. As long as what you're using is inert so that it wont leach anything harmful into your system it should be fine. However if you don't already have the sand I personally wouldn't bother. The larger disks on average probably take up a minute of my time altogether to make each... I've made hundreds which means I've spent hours creating them. A much faster thing to do which would cost about the same or maybe just a little bit more would be to buy some marble tile and cut it into small squares on a wet tile saw. Instantly you'll have little calcium carbonate frag mounts that only take seconds to make and don't need to cure for weeks. If you plan on getting into fragging a lot you'll want a tile saw anyways... Every other month Princess Auto has a great deal on one. When I run out of sand this is what I intend to do.

This is unrelated but I've been mostly using a 4:1 sand to cement mix and decided to stick with it. The disks are a little bit weaker at first but once they've cured a bit longer they are quite strong. I also try to only add as much water as I need. Using too much water so that the mixture is runny again reduces their strength.