Liverocks....

[Joe_P]

Hi Guys, got out of line from another topic in the DIY forum...

http://www.sgreefclub.com/forum/index.php?...pic=10864&st=30

and have started a new thread here regards the above mentioned....

Please do contribute regards your experience to the DIYing of rocks......

[Morgan]

Can the nitrate converting bacteria colonise the interior of the DIY rocks or it is only for decoration purpose only.

Asking this cause cement is not porous, and there is no way water can seep into the centre.

[ervine]

Actually cement IS porous... although you can't really see it but it is...

Someone should try churnning out large amounts of these DIYed rocks cure them then dunk them in a saltwater tub to make them "colonized"... them sell them at prices cheaper than normal LRs...

[BarraCudaTM]

now liverocks are selling at $4/kg already .. cant justify the cost saving with the time and effort needed.

[Joe_P]

now liverocks are selling at $4/kg already .. cant justify the cost saving with the time and effort needed.

DIY rocks in large quantity will definitely justify the cost ....

Portland Cement is cheap .......

Got 10 kg at $4....

You can get better rates if a 50 kg pack is purchased....

Only issue would be the time required to cure them.......

[Achilles Tang]

DIY Cement LR is going to be extremely heavy compared to much more lighter and more porous limestone liverock.

The curing time to reduce the high PH of cement will also take a very long time.

How much time and $ do you expect to save?

[Achilles Tang]

Do you know how much sand to use?

[Joe_P]

DIY Cement LR is going to be extremely heavy compared to much more lighter and more porous limestone liverock.

The curing time to reduce the high PH of cement will also take a very long time.

How much time and $ do you expect to save?

There are methods to get them really porous...

eg getting clumps of rock salt and inserting them into the mixture ...

the salt would dissolve during the curing period... leaving the DIYed rocks with lots of internal "lobangs"....

Someone pls confirm with this... but how porous the rocks get depends very much on the materials used eg... grade of sand mixed with the cement...... even the ratio does affect the way the rocks turn out....

One reefer in RC uses broken bits of foam in the cement mixture... thats definitely gonna help regards the wright issue....

Guess its up to us to find out through experiments here....

There are ways to speed up the curing process..... the idea is to replace the water the rocks are curing in regularly....

some one even suggest placing the rocks in the toilet.... and the stuff get a new batch of water whenever the the loo is utilised....

Utilising of vinegar to speed up the curing process helps too.....

Like what I mentioned.... time is the factor here that really determines whether this process is feasible .....

[Joe_P]

Jus to add on .....

Was wondering if the foundation of rocks are made of lighter and cheaper materials.... like foam.... and the external made by shaping wet cement/sand onto it.......

maybe the rocks would start to float.....

[Joe_P]

Do you know how much sand to use?

4 and 5 parts of sand to 1 part cement....

more cement..... rocks would be denser....

The amt of water to add the to the mix depends on how viscous (did I get the spelling right) you want it to be....... if theres too much water, shapin it becomes difficult....

[Joe_P]

The curing time to reduce the high PH of cement will also take a very long time.

How much time and $ do you expect to save?

Like what I mentioned.... time is the factor here that really determines whether this process is feasible .....

$6 -$8 per 10kg of grade 0/1 sand could get you quite alot of rocks...

esp. when a avg reef requires more than 100 kg of it.... You guys work out the equation... and you would roughly understand how much $$$$ you could save....

[Achilles Tang]

I wonder why DIY liverock have never taken off after all these decades.

[Morgan]

Where are you going to find the space and also time to first mold the rocks and then cure them....

[Joe_P]

Whare are you going to find the space and also time to first mold the rocks and then cure them....

Well, someone's 8 footer reef would be a really cool place to start off with.....

[Achilles Tang]

I can volunteer my cistern..

[Morgan]

So nice of AT to volunteered.

No way you can use my tank for curing....

Still think cement is not that porous......if you add too much sand to make it "porous". it might crumble like cookie when you pick it up or it might also slowly disintegrate when you put it into the tank.

[Tanggy]

Use rock salt to create the holes and plastic shavings to make it less heavy.

As the rock salt disolve in the water, leave behind lotsa hole in the rocks. Was seeding it in my QT but stop cos need it as temp holding tank for my LS

[Joe_P]

hmmm..... excellent...

Those DIYed rocks of your look neat.... I wouldn't be able to recognise it as manufactured stuff if they are properly cured and coralline algae covered.....

Like to list out a procedure list to help reefers here???

[ervine]

Rock salt.. good idea!! BTW, pond makers use pineapple to help cure their concrete ponds faster.... same principal as vinegar...

BTW, making concrete is almost an art... water to cement ratio is one of the factors, more water more viscous but less strength.. the other is type, size, amount of aggregate (pebbles, sand, gravel, etc) this gives other properties like texture, additional strength, etc etc..

Best way is to trial and error.. or get tried and proven recipies from abroad...

[Joe_P]

A thread from RC that I find particularly helpful in clearing some doubts...

http://reefcentral.com/forums/showthread.p...&threadid=60515

[BarraCudaTM]

using vinegar to cure the cement will weaken the structure and making it fragile. Improper ratio of water, cement and sand will cause bits and pieces to chip off when submerged in saltwater. Cement got a curing time of abt 1month and it needs to cure wet, if you bake it under the sun during the first few days, it wont be strong to hold together in long term.

Remember the DIY rocks must be able to take the weight for the pile up. If its not strong enough, the whole rock structure will collapse.

[Tanggy]

The ratio is 5 part coral sand and 1 part water. if plaster shaving is used, add it to the coral sand ratio.as for the shape will depend on the moulder liao. i delibrately made lotsa hollow passage within the rocks while I was moulding it. Trie to make the shape irregular in a regular way so it will look natural. Main thing is it can be moulde in any shape and any size to suit needs so dont have to let the rocks dictate your scapping. can make rock that interlock.

[Tanggy]

The curing of the cement has to be done slowly or the rocks will not be strong like what barra said. Also if vinegar is used, has to rinse and leave in plain water before can tell if really cured as the vinegar will drop the PH so not accurate. wouldnt want these diy rocks to fry your PH rite. My took almost 2 months to cure.

[Tango_Liverock]

How to tell whether the concrete is really cure ? Can we use normal brick as liverock ?

[Achilles Tang]

Brick as liverock???? Wahaahahaa!!