No diatoms in tank after cycle?!?!?

[Joshua Vergos]

I've been cycling my tank for a little over 3 weeks! I have put in carib sea live sand and reef saver dry rock. I have put in food every few days and have been testing the water frequently. Also I put in a ton of bring shrimp a few weeks back too so I can kick the cycle a little more! Since then I have seen a small spike in amonnia, nitrites and nitrates. Ammonia went down and so did nitrites too! Nitrates went up to 40 and now back to 5 after a 50% water change last week. I have had it on a lighting schedual too for 10 hours a day! No diatoms have bloomed I look closely and from the flakes decaying on the sand it looks close to algae but I am nkt sure if it is! I take pictures of the tank every night compare each day. Little to no change for algea growth. Any advice??? Thank you!
Salinity 1.025
Ph 8.0
Ammonia 0
Nitrites 0
Nitrates 5

 

[mich2599]

Mine took over a month to show up.

 

[lzrlvr]

They will come.