Qt startup and phosphate??

So lost all of my fish in a 32 cube due to ich. Decided to go fallow and while doing that I'm starting a 13 gallon qt tank that I hope to only observe my new tank mates in and not have to treat them. After a i qt my 4 fish I plan to add to my 32 cube I'm hoping to turn qt tank into a mini frag tank..


So a quick run down of equipment

Aio tank fluval evo 13.5 gallon
Caribsea black live sand about 10 pounds
13.5 pounds of fully cur d live rock from lfs.
Need to add a power head but not sure what size for this small of a tank?..

Starting to cycle my tank, not sure if I will see a cycle with the rock and sand both live. I threw in a table shrimp just to see how it goes. Decided to do a starting water test and ammonia, nitrites, nitrates are zero. Ph 8.2. I just added the sand and water Friday and the rock Saturday and my phosphate is at .25. Weird because all bought all the water from lfs premixed. I checked the phosphate on the left over water I didn't use and it was zero. Kinda annoying bc I really didn't want to deal with a bunch of algae. My question is high phosphate levels normal in a cycling tank bc I've never checked before. I'm used to the diatom bloom but I just really don't want to have to battle cyano again..

Can I start using phosguard in a cycling tank and is high po4 levels normal in cycling tank

Suggestions on powerhead for 13.5 gallon tank

Pictures to come

THANKS GUYS!!!