<a href=showthread.php?s=&postid=9008148#post9008148 target=_blank>Originally posted</a> by tankslave
Whether you grow algae or not later is very relative! Trust me, if I want to grow algae, I'll grow algae!
And who started this idea that the DIY rocks are going to leach nutrients or phosphate!!!?!
I'm soaking them in RO/DI (The DI is the important part) to remove any silicate and to minimize the pH swing. What Phosphate?!?
Number one, you do realize that the chemical processes that create hardened cement, do not stop just because you drop the rock in water, be it RO/DI or not, don't you? RO/DI is not a magical solution - all it is going to do is make sure you aren't adding anything else bad to the stew while you kure, such as the phosphates and all the other stuff found in most potable and groundwater. Cement has been found to still be making a chemical reaction for something like 100 years. 100 years. Chemical reactions making that cement harder and harder, and Nothing you or I can do can stop it. Period. That's why if you have ever tried to remove a very old cement pad or the like and it seemed like it was made of iron - its been "curing" all these years.
Number three, you also realize that there are a lot of chemicals/elements that
are leeched off by cement that plant life thrives on, such as lime. Is phosphate one of those? I don't know, never said it was (though I do believe that chicken feed crushed oyster shell is cleaned by chemical process and thereby sucks up some of the phosphates in the cleaning solution - which is why I don't use CO in my mix), but phosphates are only one thing that may or may not be leeched.
So, assuming our rock is still "Actively" curing, even though we have kured it, and knowing that plant life loves the very things we are trying to kure out it, which for at least a while is going to still be produced by the "fresh" cement, why on earth would you think that you aren't going to grow a bumper crop of algae?
Or cop such an outraged attitude about it?
There is a reason that the manufacturers of man made rock kure their rock for so long (Garf claims a year) before dumping it for seeding (another 6 months) - it gives the rocks time to form a layer that is nutrient reduced, and less likely to produce unwanted algae blooms when first introduced to the aquarium...
PS - a curious streak in my prompted a quick google search. And while I can't say "Cement contains phosphates", I can say that the number of states in the US that number cement in their states trade goods/resources, also list limestone and phoshates as trade goods. I live in an area where cement and limestone are manufactured and mined - the two are always on the same acreage - if this is the case with phosphate mining, you'd almost have to assume that there are going to be some phosphates in the cement manufactured at these locales.
