thanks for the quick reply. I believe the issue I am having is more along the lines of a diatom problem, the water gets more brownish than green and I think it is suspended diatoms/particulates in the water. when it is bad water changes don't do anything to clear it up.
i recently tried using "Algae Fix" which cleaned up the water, but it knocked out some of my BB colonies and then I had to deal with an ammonia spike, and since then the diatoms have come back ten fold. i have left my tank light off completely for over 2 weeks straight thinking it might stop the diatoms/brown algae from growing but as they settle out of the water it leaves almost a blanket of brown "powder" on the bottom. i syphon it out every couple of days because i know it adds to the ammonia levels and silicates in the water which will never allow the diatom problem to get itself under control. I am thinking that i need to extract the suspended diatoms out of the water in order for the cycle to regulate itself again.
the tank is a 150gal filtered by two Eheim Pro II 2028 filters which I removed the filter floss from because it was cloggin up too quickly and killing the flow rate. i may need to put some back in and see if that helps at all. the current stock is a 10" tiger oscar and two 4" clown loaches (lost 2 loaches from the ammo spike). i do weekly 50% water changes and nitrates never get above 10ppm, usually closer to 5ppm.
do you think the XL diatom filter will fix this issue if I run it for a couple hours each week after doing the water change?