Phosphates off the charts... help?

[Russ_in_Georgia]

Back again for some more learning! After learning from Master Jay about blackouts and dosing of chemicals I had relatively good luck for 2-3 months. Then wham, diatom bloom and algae shortly thereafter... Another blackout zapped most of it but the diatoms have resumed taking back over... I read up they may indicate high phosphates... So I hit the LFS this evening and pick up a test kit and a filter bag to help lower it cause I'm sure it's high... I get home, test it, and the vial turned ink blue (10ppm+++) within seconds, winner! Test the tap water, nothing.

So my questions... I do run filter cart's that contain carbon and I've learned from googling that apparently some carbons leech phosphates... Should I discontinue carbon and do 'home made' filter media or are there better brands to look for? Are there any other methods that can be used other than filter media to keep the phosphates under control?

I do weekly 10-15% changes including as much substrate vacuuming that I can without disturbing the plants. I feed the fish flake once a day (evening) and they are pretty quick to clean up the water column and are scavenging for anything that sunk well within 5 mins. Ammonia and Nitrites are zero, nitrates never really get close to 10 between water changes, usually closer to 5, PH is typically in the mid 7.2-7.6 range.

Thanks!

[Loman]

I am sure Master Jay will be along (although probably toomoorw). In the meantime one question that seems perrtinent is how often you change the carbon filter media.

[Russ_in_Georgia]

I rinse them out every water change to get the slime off them and replace them monthly

[Jay]

Are you sure it went to 10? I keep my phosphate level at 2-3 which is really blue on the chart.

The one sure way to tell is stop using the carbon for a month along with regular large water changes. Not using carbon will not hurt you. I never use it.

What nutrients are you dosing? If you are dosing as I would recommend, then you need much larger water changes 50 60 even 75% to get your tank reset and deal with nutrient accumulation. A 15% water change usually will not stop the accumulation of a DOC.

Jay

[Russ_in_Georgia]

Positive it was way over 10, this is the chart in the kit, the vial looked like I'd filled it with blue food coloring it was so dark of a blue. http://www.americanaquariumproducts....olorchart2.jpg

As far as my dosing. Daily flourish excel (5ml) and twice a week (mon eve, fri morn) on the flourish comprehensive (4-5ml) and potassium (5-7ml).

[Jay]

IMO and IME let's try this.

If the activated carbon in more than two weeks old, just continue to rinse it, as it has lost its effectiveness as a filter material and it is now just a place for bacteria to colonize..

I would start with a 50% water change, followed by another in 72 hours...test and then do another if necessary. If you are convinced your tap water is not loaded, then there are only a few sources of PO4...DOC accumulation, fish food rich in phosphates <- Read the label, PO4 dosing with no corresponding plant uptake.

Let's see what happens.

Jay

[Russ_in_Georgia]

I'll get some changes started in the AM. My father suggested the food as well, I'll read through the fine print!

[Russ_in_Georgia]

I think I found the biggest source of it all... The one piece of advice I didnt follow last time I got advice on the blackout was to discontinue use of the PH buffer... Looked at the label this morning and right on there clear as day "Contains phosphate buffers" ... Get out the test kit, test tap water, nil. Sprinkle in a few crystals of the buffer, shake up, turned to instant blue gel! Ditching that, going to get new food as well and will go from there.

Thanks again and sorry for the noise.

[Loman]

Russ thanks for sharing that info. It adds one more reasons that in most cases pH changes are not really practical