Ideas on getting nitrates up

[warriorcookie]

Agreed, some phosphates is good. But i have to run gfo to keep them below .1ppm.

And normally I'd leave it alone, but i'm trying to get nitrate off the floor. As i raise nitrate by feeding fish and corals phosphate is rising way faster.

My ideal range would be 1-2ppm nitrate and .05ish phosphate. I know I can't control that, but i'd like to get it close and balanced.

Yup skimmer is fixed and pulling some thick stinky crap out again.

[Myka]

Sounds like testing issue. Do you use the same vial of water throughout the test? Do you make sure the vial is inserted into the checker in the same direction each time?

[warriorcookie]

Originally Posted by Myka

Sounds like testing issue. Do you use the same vial of water throughout the test? Do you make sure the vial is inserted into the checker in the same direction each time?

No, I use one vial for C1 and a seperate vial for C2. I always point the 10mL label forward.

[warriorcookie]

I found some better tips from Hanna Instruments here: http://www.reefcentral.com/forums/sh....php?t=1961215

The instructions say to shake for 2 minutes, but on the forum post it sounds like it's not required.


I'll try that tomorrow with the same cuvette. I did the test again and got 5ppb (6ppb and hour before that)

[Myka]

Yeah use the same vial so the entire test.

[Myka]

Matt, did you find this article? The article is regarding elevated nitrate, but does talk about the effects of alkalinity with nitrate and photosynthesis too.

http://www.reefedition.com/nitrate-i...reef-aquarium/

[warriorcookie]

Originally Posted by Myka

Matt, did you find this article? The article is regarding elevated nitrate, but does talk about the effects of alkalinity with nitrate and photosynthesis too.

http://www.reefedition.com/nitrate-i...reef-aquarium/

Nice find! I'll read it more thoroughly later. A quick skim, this caught my eye:

Note that this process consumes alkalinity (the H+ being produced shows this). So when nitrate is accumulating in a reef tank, alkalinity is being depleted. Production of 10 ppm of nitrate will deplete about 0.16 meq/L (0.45 dKH) of alkalinity. If this nitrate is removed by water change, that alkalinity is lost forever. If the nitrate is taken up by an organism (algae, coral, bacteria, etc.) and used, then all of that alkalinity is returned to the system (see equations below showing this fact).

Curious, when I dose nitrate and the bacteria consume it does that contribute Alkalinity to the system? I know it would be insignificant. If I was dosing an additional 1ppm a day that would equate to .045dKH per day.

In most cases where nitrate levels have been examined in relation to the growth of calcareous corals, the effects have been reasonably small, but significant. Elevated nitrate has been shown to reduce the growth of Porites compressa (at less than 0.3-0.6 ppm nitrate),16,17 but the effect is eliminated if the alkalinity is elevated as well (to 4.5 meq/L). One explanation is that the elevated nitrate drives the growth of the zooxanthellae to such an extent that it actually competes with the host for inorganic carbon (which is used both in photosynthesis and in skeletal deposition). When the alkalinity is elevated, this competition no longer deprives the host of needed carbon.17

This makes sense. The higher the nutrients the higher Alk is needed. Likewise, low nutrients generally requires low Alk. Are they suggesting coral growth and zooxanthellae overproduction (browning) happens at levels of .3 to .6ppm? Anecdotal reports 1 to 2ppm being fine... Also, 4.5meq/L is just over 12.5dKH!


Anyway, I'll spend more time with it and wrap my head around it later.

Thanks!

[Myka]

Originally Posted by Ryanerickson

This is interesting as I have the exact issue zero nitrate and phosphate always .03-.07 by the way Hanna is your best bet for nitrate test kit screw the color matching game.

Hanna doesn't make a checker or photometer that is seawater compatible. The instruments can't "see" through the high TDS of seawater.

[Myka]

Originally Posted by warriorcookie

So, I couldn't find the info, but is the Hanna HI96728 freshwater only?

Yes, freshwater only. I'd have bought one long ago otherwise. That's why none of the reef stores carry it. With Hanna gadgets you can usually assume it's freshwater only unless it specifically says marine compatible.

[Ryanerickson]

Wow I assumed my buddies were using a Hanna guess not I've never invested much into nitrate because mine has always been non existent. I'm very interested in how this works in the long run sounds a lot cheaper then constantly buying rowa. I'm actually using phosphate minus by aquaforest right now and it's pretty week product vs rowa.