Excel & phosphates ?

[charlie]

Hi Tom , here is a question for you( or any other ), recently i`ve been double dosing Seachem Excel to combat a BBA out break, in so doing i decided to test my water parameters & was shocked to discover my Phosphates were above the 5 ppm scale my test kit was capable of reading, i decided to try & track down if anything i was adding to the tank was aiding the Phosphate levels apart from the regular PO4 dose as per EI, which by the way is 1/4 tsp for my 75 gln.

I started by checking my source water , which showed no detectable PO4, then made up sample with KNO3, still no Po4, K2SO4 = no Po4, Tropica plant Nutrition = No PO4, i checked everything including my dechlorinator & came up with a negative, i had put away the test kit & it dawned on me that i did not do a sample with Excel, i was surprised that the Excel sample showed up positive for phosphates, is this normal & if so should i be cutting back on the PO4 dose as per EI while dosing Excel( this tank is a 75 gln at 3.5 WPG heavily planted, EI , pressurized CO2 @ 30+ PPM )
Regards
I should add the BBA outbreak i suspect was as a result of changing the lights & co2 rig, took me a while to get the co2 dialed in.

 

[charlie]

Seachems explaination

Hi Tom , here is a question for you( or any other ), recently i`ve been double dosing Seachem Excel to combat a BBA out break, in so doing i decided to test my water parameters & was shocked to discover my Phosphates were above the 5 ppm scale my test kit was capable of reading, i decided to try & track down if anything i was adding to the tank was aiding the Phosphate levels apart from the regular PO4 dose as per EI, which by the way is 1/4 tsp for my 75 gln.

I started by checking my source water , which showed no detectable PO4, then made up sample with KNO3, still no Po4, K2SO4 = no Po4, Tropica plant Nutrition = No PO4, i checked everything including my dechlorinator & came up with a negative, i had put away the test kit & it dawned on me that i did not do a sample with Excel, i was surprised that the Excel sample showed up positive for phosphates, is this normal & if so should i be cutting back on the PO4 dose as per EI while dosing Excel( this tank is a 75 gln at 3.5 WPG heavily planted, EI , pressurized CO2 @ 30+ PPM )
Regards
I should add the BBA outbreak i suspect was as a result of changing the lights & co2 rig, took me a while to get the co2 dialed in.

I just got off the phone with a tech rep from seachem, she assured me there is not a remote chance of the product causing phosphates to rise, her take is that the product is a reducing agent & as such can mess with the Reagents of test kits, as i`m scientifically challenged , it means nothing to me, can you good folks confirm the Seachem explanation.

 

[Tom Barr]

Excel neither oxidized nor reduces chemicals. It might cause issues with the test if you add it etc.

I'm not certain.
Depends on the type/method of PO4 test done.

I'd not worry much about the PO4 reading myself in your tank.
Do a water change, say 60-70% and it should come way down quickly.

If you think about why you have high PO4(assuming you actually do) and BBA, what might cause plants not to take up PO4?

What upstream nutrients might be at play here that are limiting in some way?

Not light, not NO3 if you are dosing that, and likely not K+.

What's left?

CO2...........what is BBA linked strongly too?
Poor CO2.

So, I'd focus there.

Regards,
Tom Barr

 

[charlie]

Excel neither oxidized nor reduces chemicals. It might cause issues with the test if you add it etc.

I'm not certain.
Depends on the type/method of PO4 test done.

I'd not worry much about the PO4 reading myself in your tank.
Do a water change, say 60-70% and it should come way down quickly.

If you think about why you have high PO4(assuming you actually do) and BBA, what might cause plants not to take up PO4?

What upstream nutrients might be at play here that are limiting in some way?

Not light, not NO3 if you are dosing that, and likely not K+.

What's left?

CO2...........what is BBA linked strongly too?
Poor CO2.

So, I'd focus there.

Regards,
Tom Barr

Thanks Tom , the co2 was off beat as i mentioned , it started when i had just changed the lights & co2 rig , it took a bit for me to get the co2 dialed in, as of present , my ph is down ( checked with 2 different digital PH testers) to 5.80 at lights out, i took a sample & sat it out, when checked the following morning ( 12 hrs after) my ph is 6.85, at 24 hrs it is 7.6, so i`m assuming my co2 is pretty much up to par now.
Regards

 

[Tom Barr]

then just keep going with the good CO2, good Excel dosing and trim off the BBA as much as you can each time you work on the tank.

Bleach any non living items you can remove.
Clean tubing good, clean filter often, keep current and mixing up.
Water changes + good CO2 and picking on it will cause the issue to go away and the PO4 will not really be an issue any more.


Regards,
Tom Barr