mixing substrate

[Jamaica_sun]

Hi all. When I set up my tank I was advised my my LFO to use a wet substrate instead of sand or crushed coral.
It is black and gray peppered looking stuff.
I am needing to add more, and I was wondering if it would hurt to mix a different type of sand on top of it.Not sure if I am going to, I just want to make an educated decision. I am seriously thinking that it won't matter... but I want to be sure.
Thanks,
JS

[Bruce]

I doubt it would...but weirder things have happended Lets see if anyone has imput.

[coral reefer]

No it doesn't matter that much depending on the substrate now. Is it an aragonite based sand? If not you will need to add some to help with the buffering capacity of your water as well as the minerals in it. Also if you plan on keeping corals, the lighter the sand base color is the better as far as the light reflecting off the sand bed at the bottom to refract back upwards to the underside of your corals to ward of bleaching on the underside of your corals. ie. the underside of Acropora's and Montipora's.
Also as far as the size of the sand- their are advantages and disadvantages with fine and course sand. For burrowing inverts and fish(jawfish), it is adviseable to have some course as well as fine grains so that the hole/home of the Jawfish doesn't keep caving in. Fine sand tends to keep detritus from seeping down into the lower layers of the bed as fast as the course sand. Fine sand allows Stars, worms and sand sifting Gobi's to easier get around the sand bed. You can read more about this in most Marine Aquarium books!
I hope I helped you out alittle!

[Bruce]

I wish i had fine sand...once you have coarse sand...your stuck with it...all the fine sand sifts to the bottom and the bigger pieces get algae on them and dont look so good...but im slowly replacing Not all of course...just when it has algae on it ^^

[karlas]

im not sure what type of substrate you have right now being dark like that. but i have mixed different types of sand together with no problem arag alive, pink fiji, southdown, and anothdr type of marine safe sand i found in the lfs and have had no issues with mixing

[powdertang05]

yes that will be just fine go for it