cyano bacteria....

[Smarkalan83]

I have had tank for over year and a half and at first had cyano but got rid of it but now all of a sudden its back at least I think that's what it is...I have 2 clown fish 1 damsel and 1 hippie tang...few mushrooms 2 zoo colonies some xena and 2 duncans....my tank is 60 gallon and my levels are...
Ca 480ppm
Ph 8.2
Alk in range of 1.7-2.8 says normal
Phos .5
High range Ph 8.4
Nitrite 0
Nitrate 5
Ammonia 0
Arent these pretty good levels...3 days ago I did about 8 gal change and sucked some up but its back...here are pics...

 

[Gti_Leo]

the phosphates are not a good level
PS that hippo should not be in a 60, i would look to re home it ones it gets bigger