0 phosphates??????

[bracebldrs]

tell me how can you have alge if you test o for phos???
do i just have a crappy test its a[ hagen]brand?

[sir_dudeguy]

probably the crappy brand for one, but phosphate isnt the only thing that causes alga you know....nitrates do, and so does TDS.

Test with salifert brand tests at night (some algae releases some nutrients at night and suck em' back up in the morning)

[Amphiprion]

It could be the test kit, as sir_dudeguy said, but algae are extremely efficient at absorbing the needed nutrients. They can do it so quickly and so well, that if there is enough, you will likely never detect any phosphate. Also, test kits only test for inorganic phosphate, so any organically bound phosphates won't show up very well, if at all.

I would also look into other things, like nitrate, as mentioned above and maybe use a phosphate adsorption sponge like phosban. Do you have a protein skimmer? An effective one can indirectly cut down on phosphates.

[bracebldrs]

I would also look into other things, like nitrate, as mentioned above and maybe use a phosphate adsorption sponge like phosban. Do you have a protein skimmer? An effective one can indirectly cut down on phosphates. [/B][/QUOTE]

my nitrates test 0 [salifert ]my skimmer is a css220 which has been disapointing me lately.either skimming to wet or barely
dry .i run a mag350 on the side /carbon guess ill toss some phos
ban in tomarrow.would i have to install a tds meter on ro unit?

[sir_dudeguy]

ya you cant really do the tds test on water already being used i think, because salt itself would be a "dissolved solid," no?

so ya you gotta do it on the RO water i believe.

[danch]

Most of the test kits sold to us only test for orthophosphate. There's a lot of phosphate that's bound up in organic molecules.

[dwculp]

More than likely your problem is what was mentioned above, your phosphates are being absorbed by algae so quickly that you essentially have no PO4 to detect.

Try using a PO4 absorbing media like Phos Ban.