The phosphate level in my tap water!

[99RedSi]

Is 0.30ppm of phosphate straight out of my city tap water going to cause me algae problems in a freshwater aquarium? Nitrate is 5.840ppm, btw.

I haven't started my aquarium (55g) because I'm not finished researching everything on God's green earth.

I've got three options:

1) Non-planted tank with just "nutrient suckers" to prevent a large amount of algae growth on gravel, glass, etc (Hornwort is what I had in mind, mainly).

2) Planted tank with a C02 injection setup

3) Saltwater tank (live Rock/live Sand - no corals)

4) African Cichlid tank (all rock tank)


Thanks guys :)

[wetmanNY]

All plants are "nutrient suckers." I have a hunch that you have highly alkaline water (that is high "KH"). The high KH will guide what you do, more than some PO4 in your tapwater.

If you dosed potassium, in a planted tank with decent lighting, the plants would take up that phosphate. Other people are actually dosing PO4.

Your KH will decide the question.

[99RedSi]

wetmanNY -

Thanks for your help. I'll go buy a KH test kit either tonight or this weekend and post the results!

Thanks again! :)

[99RedSi]

wetmanNY -

I bought a KH test kit and I have a KH of 10 straight outta my kitchen sink tap-water.

What do you think?

Thanks

[wetmanNY]

Well, 10 dKH, degrees of "carbonate hardness" is 10 x 17.86 or about 190ppm. Pretty well buffered. That figure is including some other anions, like your phosphates. Plus hydroxides and some rare stuff (borates?)

There is good water chemistry material at theKrib, especially http://www.thekrib.com/Plants/CO2/hardness-larryfrank.html but other pages there as well. Bookmark theKrib.com.

The water chemistry stuff at www.skepticalaquarist.com is improving.

I definitely think all your options are open, so you have to make the basic decision of what kind of microworld you want to look at.

BTW, unwashed laterite (or lightly rinsed if you must), whether baked (more manageable) or unbaked (scorned by some as cat litter)-- laterite mixed in your substrate helps reduce algae-inducing PO4 in the water-- even if your tank isn't planted.

But there are products like Phos-Sorb that can help too.

[99RedSi]

So my phosphate level is pretty high then given my KH?

[wetmanNY]

Not at all. But I think our PO4 test kits and our amateur testing procedures (do you rinse the vial off in distilled water and store it wet? I know I haven't.) are more misleading than useful. If you really have <1ppm PO4, you might even wind up dosing it if you have a planted tank. That's pretty low phosphate --if it's an accurate result.

Not to worry.

Do other folks agree?