Green hair algae and more

[spyglass]

Hi to all,

Is it possible to have very low levels of phosphates and nitrates (almost undetectable) and yet have green hair algae and other diatoms ? Or its likely to be a

case of expired test solutions that give false reading of phosphates and nitrates?

Currently seeing green hair algae and reddish algae causing my sand to clump together. Despite washing them it comes back again.

Thanks

[allantang]

my PO4 n NO3 is 0. still green hair algae grows.. gotten some snails n abalone to do the clean up job..