stupid question

how new is it? if its really new, you'll have to wait for the tank to establish the beneficial bacteria that convert ammonia to nitrite to nitrates. This can be a week to several weeks. 

you're probably building the bacteria still. what kind of rock did you get for it?

sounds like you're still in the cycle with the fiji then. just be patient and the ammonia will go away.. just watch for it and the nitrites.. when the nitrites go, you should be good to add some animals. 

nitrates will be reduced by macro algae.. so if you dont have any (which i think you said you did) then get some.. chaetomorpha is good for it. 

probably around 15 watts should work.. maybe wait for someone who has some in a sump similar to yours to chime in before taking my word for it though.. 

actually, i just noticed its a 30 gallon sump.. so at least 30 watts of CFL.. 

Typically when you bring in new live rock there is some die off of organisms on that rock that occurs.  When these things start to rot they produce ammonia.  There are bacteria on the live rock that will consume ammonia and they produce Nitrite as a waste product.  Ammonia is very poisonous to fish and motile inverts, including your snails.  The problem with a new tank is that there is not enough ammonia eating bacteria to eat up all of the ammonia that is being produced.  It takes time for the bacteria to multiply to the point that it there is enough to eat up all of the ammonia.  It will happen, but depending on the amount being produced you may have to wait a while.  Say up to a month or so, but as little as a few days depending on the amount of ammonia being produced and the amount of bacteria already on the rock and sand.  The only way to tell when the ammonia is coming down is to test.

So anyway, now you have Nitrite, which is poisonous, but not as poisonous.  It just so happens there is also bacteria that eat nitrite, and you have to go through the same process with these bacteria.  The good thing is that they are reproducing at the same time as the ammonia eating bacteria so after the ammonia is gone you usually only have to wait a few days for the Nitrites to go too.  Again you have to test to know it is gone.  Nitrite eating bacteria produce Nitrate as waste and though it too is poisonous it is MUCH less so than Nitrite so even if you have some Nitrates in your tank you can still have healthy fish and motile inverts.  (Shrimp, crabs, snails, etc.) 

Nitrites are removed in 2 ways.  First of all there are also bacteria that eat Nitrate, but these bacteria live in low to no oxygen zones, so in our tanks that means deep inside the rock and under deep sandbeds.  These bacteria tend to take their time about eating the nitrates, mostly because the nitrates take their time getting deep enough in the rock or sandbed that they can be eaten.  The second way is to do water changes. 

As I said Nitrates are not nearly as bad as Ammonia and Nitrite, in fact they have been as high as 100 ppm in my tank with only slight effects to the inhabitants of my reef.  It is suggested however that you don't let them get any higher than about 20 ppm and lower is even better.

Once your tank is fully cycled, which means that all of the bacteria has populated to the point that it can handle all the Ammonia and Nitrite being produced in your tank, you are ready to add fish and motile inverts.  The proper readings on your test kits for a tank in ready mode are:

Ammonia - 0 ppm
Nitrite - 0 ppm
Nitrate - less than 20 ppm

As for using algae, yes, algae will consume Nitrate.  It will also consume Ammonia and Nitrite.  In fact it would prefer ammonia, so adding some algae is a great way to help eat up those excess nitrogens.  We typically suggest using Cheato because we have much less problems with it polluting our reefs somewhere down the road, but the faster growing caulerpa algaes will take up these nutrients faster in the beginning.

As for corals, yes corals will also consume these elements because most of them photosynthesize and the algae that grow in them consume them just like macro algae.  However,  I suspect that high ammonia and nitrite concentrations can also be bad for the corals and I'd much rather be patient or try some algae than try corals, even cheap ones, and have them die on me.

At any rate keep testing and pretty soon you'll see your ammonia and nitrite readings at zero.  Honestly, right now the best thing you can do for your aquarium is be patient.  I know it's hard, I've been there and done that and lost patience myself, but you really will be much happier putting corals and fish in your tank a month from now and having them survive than putting them in now and watching them die. 

how southern Utah are you talking about?

how long can you wait? I go to milford once or twice a month.

how much and what type of live sand do you need?