Algae in my Flourish Nitrogen Bottle?

[The Rockster]

Hi,
Please bare with me.
This question is rather labor intensive for me. This will be my 2nd attempt to get this question answered, the first getting no response in a PM to tech support (months ago).

Background:
For the last 4-5 years this is how I have been dosing your full line of liquid ferts. During this time, I have been through numerous types of algae problems. I am sure none of them were caused by the ferts, or the dosing strategy suggested by Seachem (most were fixed with CO2, & new bulbs).

Initially, I purchased small 250 ml of each of your ferts. After trying them, and depleting the ferts, I bought 2 Liter bottles of each and reload the smaller bottles for daily use. I also bought feeding syringes (2), from a farm supply website. I use these to measure out the ferts., and dose the tank.

First I pour some ferts into a little saucer, then suck it up the syringe, and release the fert back into the dish, to get the air bubble out of the syringe, then refill the syringe and dose the tank. The excess in the dish gets put back into the 250ml bottle via a small funnel.

Over time, although presently, I really don't have a huge algae problem in my tank, I have noticed that I have black material floating in my Nitrogen bottle. It looks like algae to me.

Is it possible that BBA or some other form of algae is alive and well in my bottle of Flourish Nitrogen??

Am I adding algae as well as Nitrogen when I dose my tank?

Thanks, Inquiring Minds Would Like to Know!!!

[Tech Support LK]

Hello,
I apologize that your question was not answered through a PM. Do you remember which TS user you sent the message to?
It sounds as though the contamination from using the syringe has caused some growth in the bottle. You have likely introduced some microorganisms from your aquarium to the bottle of Flourish Nitrogen through this procedure. The growth is more-than-likely an innate mold of some sort and I wouldn't worry much about causing any issues (algae-related or other). In the future to avoid this, it would be best not to add the leftover nitrogen back to the bottle. This should prevent it from occurring again.