Here ya go boss.

It is very simple. Only 3 ingredients. I buy Portland #2 cement. It really doesn’t matter what number it is, but I prefer that kind. Do not get any premixed concrete kits, only pure cement. Then you have some options for the second ingredient. you can get aragonite sand, pure quartz silica sand, crushed coral sand, or crushed oyster shell (get the oyster shell from a farm feed store, it is used in chicken feed). Aragonite is expensive in large amounts, silica sand is hard to find, and the other two are cheap. The third ingredient is water (only use fresh water throughout this procedure). I use tap water, and treat it with water conditioner to get rid of chorine and chloramines.

Now what you do with it:

1: Get a large bucket for mixing your concrete. Get maybe 2, twenty-five gallon Rubbermaid containers. And buy some (maybe 3 or 4 bags) regular play sand. (It is in the same row as cement usually)

2: Mix your ingredients together in the large bucket. The ratio I use is roughly 1 part cement, 4-5 parts or your second ingredient (silica sand, aragonite sand, coral sand, or crushed oyster shell). Then add water till it is about the consistency of cottage cheese, maybe a little bit wetter than cottage cheese.

3: Once you are sure it is totally mixed, set this bucket aside briefly to prepare the Rubbermaid container(s).

4: Take a Rubbermaid container, and spread a layer of the play sand you purchased over the bottom of it. Make the layer about 3 inches deep. Damp the sand with water, and create groves, holes, crevices and all sorts of textured marks in the damp sand. This will be the bottom of the cast for your rock. Using more dampened sand, make high walls, to be the sides of the rock.

5: then, using your hands (rubber gloves should be worn, due to the pH of the mix), or a plastic cup, scoop out some of your mix and pour it onto the cast you created in the wet play sand. Then, using more play sand (dampened), cover the mix.

Repeat steps 4 and 5 over and over, making different shapes and sizes of rocks. Once you have filled up the first layer with different rock molds, cover it completely with sand, and start a new level of casts. You can make nearly any shape you want, but don’t make pieces too thin, as they may break, or not set up properly

Let the rocks sit in the sand for about a week, in a dry place, as to let the damp sand dry and the concrete mix to harden and dry. After a week or more, carefully dig up a piece, and test its integrity. Make sure it doesn’t easily break. If it crumbles when you squeeze it or try to bend it, the batch you made is either wet still, or had too much of ingredient two, and not enough cement.

Once you have a good, strong batch, don’t go throwing it into your tank, because it will result in the death of your fish and inverts. Now take that other big Rubbermaid container, and fill it about halfway with water. Fresh water only. Place all your newly made rocks into this water, making sure they are all covered.

This begins the "Curing" process. You will need to leave the rocks in this container for at least 3 weeks, but the longer the better. You must leave them in there because the rocks will have a very high pH. If placed directly into a tank, the pH of the water will skyrocket, and you will loose your fish.

Perform 50% freshwater changes every week during this curing process.

Test the pH of the water after a few weeks and make sure it isn’t astronomical. Once it is down to an acceptable level, it is ready to be placed into your tank.

The rock at this point will be a brown/tan or white/grey color. Don’t worry about this. It will change. Once you go through your nitrogen cycle, and the green algae and brown diatom isn’t a problem anymore, but some good, high quality pieces of live rock. Pieces with lots of coralline algae, worms, and other goodies. Place these pieces in front of power heads, so that the algae may blow around the tank, and be seeded onto your homemade rock. It will take a few months for them to start to look purple and get some worms, but it will happen, especially with dosings of Purple Up.

After making a few batches, I got creative. I took some boring rocks, flat pieces or plain round ones and drilled holed in them. I used masonry bits and an electric handheld drill.

I hope this is helpful to all the people who are interested in making their own. If you try it out, and find out any new little ideas or pointers, message me and tell me.

i am so doing that this week... but can i put the rock in even after my tank cycles... right now my tank is a fish only tank... i don't even have live sand in there... i was going to get fully cured rock later on from another tank that has been running for years...


so now i have damsels, and the cycle just started... can i still put them in after they have been cured and stuff...? will it make my tank cycle again...?

say i make 100lbs of this rock and seed it with 20lbs or so of live rock... will i lose any fish, or will it be hard to do...???


kthxbuh-bye...

NOW THAT IS SOMETHING!!! HATS OFF !

so long as the pH of the freshwater that the hommade rock is curing in is down to an acceptable level, you can add it straight to an already established tank.

your tank shouldnt go through another cycle. but note i said "shouldnt", not the word "wont". it ma go through a mini cycle if the pH of the rock is high and cause some die off of microorganisms in ur tank.

if you want to make 100 pounds of it, good on ya mate. ive never made that much for a single tank, but ive made about 200pounds and given some to friends, and put some in my cichlid tank.

20 pounds of good purple liverock is more than enough to seed the tank. but remember to place them close to the powerhead, so that coraline algae can blow around.

If anyone has any other questions, feel free to ask. or if u need more clarity of my directions.

thanks singapore...

i dont see why it wouldnt work. ive never tried putting pvc pipe into the mix, but give it a try and tell me how it works.