Phosphate Bloom and Ick

[Magicide]

For the past few days the fish have been a bit lethargic so I did the full battery of tests in the middle of the week instead of on the weekends like I normally do. I found the PO4 levels were beyond what the test kit could measure. So I did a 50% water change and tested again. Still the PO4 is showing max on the kit. Another 50% change and it still maxes out. I don't over feed, the food never makes it to the bottom, so I don't know what the source could be. I don't see how to get rid of the phosphate in the water other than letting the plants do their job and keep doing water changes until it drops. I tested the tap water and it measures zero PO4 so I know it isn't coming from that source.

Now to make it more interesting my Cardinal Tetras are starting to show signs of what appears to be ick the day after I did the first 50% change. It appeared literally overnight and since it appeared 2 days ago I have lost 3 of them and most of the rest have spots on their bodies but are otherwise acting normally.

I have also lost 3 Juli Cories in the last week, since every single other water test I ran came back in the acceptable limits I have to assume it's either disease or PO4 doing it. The Angelfish in the tank are acting exactly the same as they have all along and are not showing any signs of ick.

So first off other than water changes can I do anything for the PO4? Also besides lethargy what does excess PO4 do to the fish?

Next what can I do to cure the ick? I have a heavily planted tank so I am wary about using medicines to cure it since they seem to have a negative impact on plants. I normally run the tank at 28 degrees Celsius so the suggested raising temperature to 29 doesn't seem to do much. If I can confirm that the salt won't hurt the plants much I'll add in 2 tablespoons/gallon as suggested by google searches on ick.

I did add some new plants to the tank over the weekend. I bought two of the new plant bundles from Aquagiant. The plants themselves seem fine so I don't know if they could have acted as the carrier for whatever is causing the Tetra's problems or if they could have somehow spiked the phosphates.

[Blue Ram]

I successfully treated a 20 gal fully planted tank stocked with tetras & german rams with "Quickcure" (malachite green & formalin). I followed the recommendation on the bottle to dose half the recommended amount for the tetras. I treated for 7 days with no losses and no negative impact on the plants. Good luck with your treatment!

[Vallisneria]

Do high PO4 levels affect fish?I"ve never heard anything about this so i'm just wondering.

I ran came back in the acceptable limits

Can you please post the exact results.

Also have you done anything to the tank lately? Added new fish, new plants?

[Magicide]

Everything I've read says PO4 doesn't hurt fish, it just makes them sluggish. At the same time I have a tank full of stressed out Tetras suffering from ick that seems to say otherwise. Came home tonight to 5 of them floating and the rest starting to show white spots too.

The Hagen test measures in mg/L from 0.5 to 5.0. I'm sitting at 5.0 according to the test but it must be much higher since a 250% water change over 5 days still can't bring it down.

I've got a phosphate absorbing pad in my filter now and I added some java moss and (sp?) hygrophelia since they are known to absorb it as well. I will be doing 10% daily changes until it gets back into a reasonable level. I would love to know how it managed to spike so high and so suddenly when I am not over feeding nor did I have dead fish/plants polluting the tank.

[jvision]

Have you been adding any ferts? Do you use anything to lower pH? Have any kind of 'mystery rock' that could be leaching?

These are all common sources of PO4.

[Magicide]

I have used LFS peat moss to stain the water but that's been in the water for 3 weeks now. If it was going to do this I would have thought it would do it from the start.

No fish were added though I did add in a few plants from Aquagiant. I am using Nutrafin Plant Grow fert but it has zero Phosphorous content so it didn't come from there.