need some advice asap on adding new substrate to my cichlid tank

[kufan]

I have a 75 gal cichlid tank and im wanting to take out my gravel and use pool filter sand...is this a good idea...i love the white sand look...have asked my local pet store here in kansas city and this is what they told me...i will have to add the beneficial bacteria and ph buffer....how often will i need to add these and what other advice can you give me?...im plannin gon doing this on saturday....if i do add the pool filter sand and add the other stuff, how long will i need to wait before i add my cichlids back to the tank?...was told about an hr or so?...i would appreciate any tips or advice you guys have and your past expeirences....thanks in advance