Sand Bubbles...a quick question.

[kidafius]

O.K. I know bubbles in the sand are indicators that the DSB is working. My question: are the absence of the bubbles against the glass an indicator of the DSB NOT working?

This is day 34 of my cycle, and the nitrates have gone from 80+ and down to 20 and seem to be hovering between 15 and 20ppm. I used 200lbs. of playsand, and added 30 lbs. LS, and mixed it in around the top 2" of sand. I have 130+lbs. of LR (119 Gallon tank) and about 90 circulation. I haven't added a Protein skimmer yet, Could that be my nitrate problem?

sorry, I snuck two not-so-quick questions in.

 

[kidafius]

The nitrates have been around 20 for about 2 1/2 weeks now.

 

[By-Tor]

Im not convinced that bubbles in the sand are always indicators of anything. Aragamax is notoriuos for not allowing water to properly permiate through the sand bed. Thus it can create the illusion that there are nitrogen bubbles building up in the sand. Do you have anything in your aquarium that burrows and stirs the sand. If you did, and excess bubbles were released because of that, then you would know in the future if it was actually working.

 

[Gauge]

This is all hearsay, so don't assume this is right, but...

I hear the reason that DSB's work is that the bacteria in the lower portion of the sand does not get any circulation to speak of, so the oxygen all gets used up and they somehow supplement it with nitrates. Otherwise the bacteria does not process the nitrates at all.

If this is the case, then you know your DSB is doing its job in some fashion because your nitrates went down. In my FOWLR they only go up except for water changes. Also, if that's accurate the bubbles against the glass would be in no way caused by denitrification.

Protein skimmers, as I understand them, don't remove nitrates, but remove disolved organic compounds from the water, which somehow promote or produce nitrates.

 

[Mudshark]

The best way to get rid of Nitrates is through water changes... or let Algae consume it.
You can "plant" some in your Fuge or sump. It helps a bit.

 

[BillyZ]

kidafius. You are in the final stage of your cycle. At this point a water change is recommended. This will help drop those last few points of nitrates. In this stage the bacteria now has a foot hold but will continue to grow some and you can expect your nitrates to drop, hopefully, just a little bit more. But many folks always see "some" amount of nitrates and regular water changes help keep them from building up.

Do you have any other equipment attached to your system for filtering etc? A skimmer may help some by helping to remove DOCs from the water. but as I said, you're getting close to your final numbers.

 

[By-Tor]

Gauge, I think your right in your assumptions. I have read that nitrates can be removed from one of four ways. 1 - water changes....duh. 2 - live macro and micro algae. 3 and 4 low/no oxygen environments that contain a different type of bacteria other than normal nitrosynomus <--sp. and nitrobacter. These bacteria contained in low/no oxygen environments do not feed on ammonia and nitrites. They only consume nitrates. The funny thing is, last I read, scientist hadn't identified the bacteria that perfroms this great service.

My two cents....take it for what its worth