Where do phosphates come from?

[frostby]

...and is there a test for them? Is it true that .5ppm and1.0ppm for planted tanks is best?

Is a nitrate level of 30ppm, too high? Am I encouraging algae with this value? Is 10 better? And, is the only thing to do to reduce this is more frequent wter changes.

-oh yeah 60 watts normal flourescent on a 55gal.

[An t-iasg]

Phosphates most usually come from fish food. Look at your food container - it will say something like "phosphates not more than 9%", or "max. ash content 9%".

There is a test from Aquarium Pharmaceuticals.

http://www.aquariumguys.com/phosphatetest1.html

I have used it a few times but I do find it hard to match the colors. It seems to be accurate at low levels - at 0, .5, or 1.0 ppm, it looks accurate, but sometimes it shows a color that isn't even on the card. At that point I figure my level is too high and I do a water change.

Phosphate levels should correspond to nitrate levels like this: At 5 ppm nitrates, your phosphate level should be .5 ppm. At 10 ppm nitrates, the phosphate level should be 1.0 ppm.

Your lighting is low, so maybe that's why the plants aren't using the nitrates faster, and your level is a bit high. I try to keep my levels at 10 ppm nitrates and 1 ppm phosphate. If your nitrate level is higher, your phosphate level needs to be correspondingly higher. I don't know that a level of 30 ppm nitrates is necessarily bad unless you have sensitive fish like otos. I have had nitrates up to 50 ppm, with phosphates of 4 ppm, with no algae issues. I had no fish in the tank at that time!

The only way I would recommend to reduce phosphates is to do more frequent water changes, don't feed as much or try to find a food with less phosphate. Are you overstocked by any chance? I would not use the phosphate-removing chemical media in a planted tank.

PS. While it's probably not likely, your tap could have high phosphates. Do you live in an agricultural area - runoffs from farms and fields could get into your water supply, possibly, if you have well water.

[frostby]

Really, THANK YOU for your responses. I can't begin to explain how valuable this is.

My goal, is to eliminate or reduce the large amounts of BBA and brown algae in my tank, I'm trying to find my "hole" where the plants are weak, and the algae is strong. My crypts grow like weeds, but shortly get covered with algae, my swords - well they really need help.

I'm going to do my best to start another thread with pics.

SO far I've been dosing "leaf zone" that is mostly potassium and iron. I obviously don't have an issue with insufficient nitrates - and probably not phosphates. I've added CO2, and well, need to test again to see where that lies.

I use city water, 1/2 hard 1/2 outof the water softener, but the hard stuff is off the scales. I'll save these details for another post when I can add pics.

Again thank you An t-iasg

[Lonewolfblue]

Another thing to consider for the swords. Get some root tabs. They are heavy root feeders, and need nutrients in the substrate. Also, high iron can also cause algae. You may not need as much iron as you are dosing in the Leaf Zone, and will need to dose some extra Potassium, as in K2SO4 from Greg Watsons or just Flourish Potassium. Not the regular Flourish, but the Flourish Potassium, which is just potassium. Extra Potassium will not harm anything as well, is hard to overdose, and too much doesn't cause algae.