skimmerless tank with no water changes

FarmerTy · Jul 30, 2015

jared graves said:
also your live rock looks like very large pieces I use lots of smaller ones for more surface area for bacteria.

What you should also account for is nitrification is an aerobic process which requires oxygen. The bacteria that colonize the surface of your rock and the outer edges of the rock perform nitrification due to availability of oxygen. So with more surface area, you're actually more efficient at converting ammonia/nitrites to nitrates. Hence the rise of bioballs for freshwater systems. Their goal was to process ammonia and nitrites as quickly as possible to a lesser toxic form as nitrates and they accomplished that by increasing surface area.

In saltwater systems though, processing nitrite and ammonia is not as difficult. What we run across is being too efficient at converting ammonia/nitrite to nitrate and having a nitrate problem.

With bigger rocks, you have areas in the depths of the rocks that perform denitrification, as it is an anaerobic process, without oxygen. Only in the areas where there is a lack of oxygen can denitrification occur. So the bigger, thicker rocks actually are more beneficial in my opinion for saltwater setups, as they do their share of performing both nitrification and denitrification.

TheSaint216 · Jul 31, 2015

Randy Holmes-Farley · Jul 31, 2015

Oceansize said:
Absolutely correct. No argument here. I hope I did not imply anything different. If a system needs less alk added as a result of a certain process, I consider that process to be "buffering" the alk. So in my mind, a system that allows me to dose less alk than I normally would is indeed buffering that system. But no, in this case it should not be construed that the denitrator _completely_ buffers the alk...alk still needs to be added. Ah semantics. :)

Maybe we are just misunderstanding each other, but I don't think it is just semantics. If you removed the denitrator entirely, you'd need even less buffer. So it is not as bad as it might otherwise be without the aragonite, but it isn't a plus for alkalinity. Your sulfur denitrator plus aragonite is still a consumer of alklinity.

Oceansize · Jul 31, 2015

I guess I'm calling it semantics because we both agree that Alk still needs to be added to a system with a sulphur denitrator, despite the presence of aragonite in the denitrator.

Randy Holmes-Farley · Jul 31, 2015

Oceansize said:
I guess I'm calling it semantics because we both agree that Alk still needs to be added to a system with a sulphur denitrator, despite the presence of aragonite in the denitrator.

OK.

Happy Reefing. :)