algae problem

[Garbis]

Hi all, I just change my sandbed. My old one was a medium size grain about 0.5 cm each(0.2inch).the new one is bahamas oolite which is a very fine sand ranging from 0.1 to 1 mm.of course I changed 25% at first then after a week I changed another 25%.after a few days I started seeing algae on the sand bed and on the live rock too.my nitate level is 0(salifert test kit).it seems like cyano.I keep on blowing some water on the live rock with a turkey baster and all I see is bubbles and a lot of debris...and I repeat this everyday. What is this? Can somebody help me?

 

[garzaci]

Maybe something in the sand. If that's the case it might take a while to works its way out. Also, you could have had nutrients in the old sand that made its way into your water column when you disturbed it.

 

[chuckreef]

I would think its more about nutrient distribution/compettion. If we presume all of the old sandbed (at least all of the upperlayer of the old sand bed) was colonized by a large bacterial population that was continuously using nutirents in the water column to survive, then we must deduce that you rapidly removed that nutrient sink. So now,as a result: 1) those nutrients are building up in the water instead of being consumed (by the bacteria; population that was previously present), and 2) all of those nutrients (in the water) are now more readily availbale to the new algae (or cyanobacteria) that you are seeing, as this new stuff has much less competition for those nutrients. In time things should balance back out as the sandbed becomes colonized again.

 

[seabayaquatic]

Let it run its course. You have a recolonization of bacteria going on to replace what was taken out with the old sand. Add some ferric oxide just in case the new sand contains a small amount of phosphate or some was released when you disturbed the old sand bed. A water change may help too.