Bio Pellets finally working

[rodgerrr]

I've got a 300 gallon, 10 foot long aquarium that has a big bio load: 1 8" crosshatch trigger, 7 full sized tangs (sohal, powder blue, 2 sail fins, others) and about 6 other misc fish. It is also full of LPS, SPS, one 10 inch deresa clam and bunch of live rock. The tank has been running for about a year - most of the rock was moved from two other aquariums that were torn down.

I knew I'd be fighting nitrates so I'm using a MRC Orca Pro 1.5 skimmer which is a real beast. I run about 2000 gallons an hour through my sump. My normal routine calls for changing out 50 gallons every two weeks. Even with that I started to fight high nitrates, in the 25 ppm range which I did not like. So I added a RO 120r bio churn reactor loaded with bio-pellets about 6 months ago - and it effected nothing. I checked my phosphates, they were high (around 0.50 PPM) so that was not the issue. At the same time my tank was clean - not one bit of algae - which did not compute either. I was getting frustrated and started reading a lot of stuff and came to the conclusion my issue might be low iron. So I started dosing iron and changed from using kalkwasser to using seal-lab 28 blocks and reef builder - just tested my nitrates, at 10ppm and coming down. I'm happy - thought I'd throw this out there for others who have not been able to get bio-pellets to work.

[bertoni]

That's interesting. I am not sure whether the timing is a coincidence or what might have happened. Iron definitely can be a limiting nutrient for photosynthesis. It might have other effects, as well. I'm not sure on that.

[Dan_P]

Check out this paper. Iron + glucose, not iron alone, stimulated bacteria growth in nutrient limited ocean water. I have been putting off iron dosing (just to see what happens), but now I may just do it.

http://aem.asm.org/content/66/2/455.full