Low nitrates, is my refugium just draining the tank?

[October Sky]

I have a Hannah Checker and Red Sea kits, and I swap between them because I can't figure out what's going on. If the number below has a decimal, it's on the Hannah Checker.

Here's my numbers:

* 3/29 5ppm
* 4/3 5ppm
* 4/9 1.8ppm
* 4/14 3ppm
* 4/16 3.2ppm (This is the day the Chaeto was added).
* 4/21 6.4ppm (here I added Chemipure Elite because I had it).
* 4/23 4.5ppm
* 4/25 3.3ppm
* 4/30 .4ppm, .4ppm (tested twice because what the heck?), less than 1 ppm on Red Sea. Reduced refugium lighting and started feeding way more (2 clowns and inverts). Pulled the Chemipure.
* 5/11 4.9ppm
* 5/18 5.4ppm
* 5/28 1.6ppm (Chaeto has at least doubled in size)
* 6/3 .1ppm (Red Sea shows nitrate exists, but almost not detectable)
* 6/16 1.8ppm
* 6/22 2ppm

For phosphates, the numbers correlate to the nitrate, but range between .08 to .02, it's currently at .04 on 6/22.

Some notes: Tank launched on 3/19/22 with rock cycled in a Brute. When I assembled it all, I dosed ammonia to be certain it was cycled. 40b with 20l refugium, skimmer, cheato with cheap LED light on for 6 hours at night (it used to be more, but the nitrates bottomed out). For food, I use a variety of pellets, and feed Rods frozen.

What's in the tank? See photo, plus two Rock Flower Anemones. In terms of algae, I have a waning diatom bloom, and some turf on the highest rocks (you can see it in the photo, it's not long, it's like a 5 o'clock shadow on the rocks) because of the lighting (Kessil AP9x). I lowered the light intensity and raised it higher above the tank, which has certainly fought off the algae, and the coralline is now overtaking the green.

If you need any more information please let me know.

 

[ZombieEngineer]

Cut your photoperiod down to 8 hours for the fuge. Use that and/or intensity to adjust the nitrate drop until it hits an equilibrium.

 

[October Sky]

Cut your photoperiod down to 8 hours for the fuge. Use that and/or intensity to adjust the nitrate drop until it hits an equilibrium.

I'm at 11pm on, 5am off. I had it for 10 hours, then 8 and now 6. The reef lights are on from 10:45am until 9:30pm.

 

[ZombieEngineer]

Another thing to check Then is make sure you have enough CUC to keep the main tank algae down. That can sometimes artificially suppress nitrate and phosphate readings.

For a CUC I like (per 50 gallons)
5 trochus
5 more trochus or 2 mexican turbo
20 cerith
15 blue leg hermits
15 nassarius
1 small urchin (need corraline before adding this)
1 emerald crab

You also might just need to feed more.

 

[Jekyl]

3 months hasn't even really gotten you to the ugly phase yet so I doubt algae is a problem for you currently. Most likely just normal amount that all of us go through. Heavy in, heavy out is the best of circumstances for a reef tank. Keeping the chaeto growing has multiple good reasons to do so while reducing the photo period only solves 1 thing. If it were me I would be dosing live phyto daily. This will slightly increase nitrate while combating algae. If still not enough, then increase feeding. You just need to find your comfortable middle of the intake/outtake of your tank.

 

[Lavey29]

Just seems like your tank is moving along as expected. I had to double dose neophos and neonitro for multiple weeks before I got measurable numbers that eventually stabilized.

 

[GARRIGA]

I question the theory that light output impacts nutrient uptake by algae based on reading "Ecology of the Planted Aquarium" by Dana Walstad. Recall her saying that plants consume nutrients 24/7. Photosynthesis where energy is converted of those nutrients pulled 24/7.

Been a while since reading it so my memory could be wrong.

 

[October Sky]

3 months hasn't even really gotten you to the ugly phase yet so I doubt algae is a problem for you currently. Most likely just normal amount that all of us go through. Heavy in, heavy out is the best of circumstances for a reef tank. Keeping the chaeto growing has multiple good reasons to do so while reducing the photo period only solves 1 thing. If it were me I would be dosing live phyto daily. This will slightly increase nitrate while combating algae. If still not enough, then increase feeding. You just need to find your comfortable middle of the intake/outtake of your tank.

That last part is what I'm trying to achieve.

I was dosing phyto when I started the chaeto, as I got it with the chaeto. I believe I can grab some phyto from my LFS.

 

[Jekyl]

That last part is what I'm trying to achieve.

I was dosing phyto when I started the chaeto, as I got it with the chaeto. I believe I can grab some phyto from my LFS.

I was using the stuff from algae barn for a long time. Great for the tank and was awesome for eliminating random algae.

 

[October Sky]

I was using the stuff from algae barn for a long time. Great for the tank and was awesome for eliminating random algae.

Ha, that's what I wanted but they were out of stock, so was pretty much everyone. Got it from Aquarium Depot.

 

[ReefGeezer]

Is your Cheato even growing? Looks like there is one only fish in the tank. If so, nitrate and phosphate is going to remain low with so little organic input, even without the Cheato. I don't know what your fuge consists of, but it may not really be doing much at the moment. What N & P are developed by the one fish and a little from decomposition of uneaten food is probably handled by the rock right now via denitrification and binding of the phosphate. This will change as you add more fish to the tank and the bound phosphate level rises on the surfaces of the rock.

And... Just my opinion... All is well as long as there is some detectible N&P. Within reason, the number doesn't matter. I would not do anything as long as the nutrient level trend is not rising. Your tank is only 3 months old. Nutrient levels will start rising soon enough.

 

[October Sky]

Two clowns, although I'm contemplating a six line, but gotta get my lid installed.

The Cheato was golfball sized when I got it, it had some die off, and now it's golden.

EDIT: You can see the grow light in photo 4, it's 4.7" wide. So the Cheato is wider than that.

 

[ReefGeezer]

Two fish is still not a lot for a 40. The little bit of Cheato in your sump is probably not limiting the N & P very much. It's great that it is growing some but there it is just not a lot of it. Looks like you have some Coralline growing. That's a good sign. You have a reasonable amount of rock in the display and sump, and have a good skimmer that is running pretty wet. Those are the reason for the low nutrient levels. That's great for now. Your Cheato will grow more as more organic input from feeding more fish results in more nutrients to being introduced than the rock can control.

You could adjust the skimmer to run a little drier, but otherwise I would still not change anything until you add more fish and start to see nutrients rising to much.

 

[Lavey29]

I question the theory that light output impacts nutrient uptake by algae based on reading "Ecology of the Planted Aquarium" by Dana Walstad. Recall her saying that plants consume nutrients 24/7. Photosynthesis where energy is converted of those nutrients pulled 24/7.

Been a while since reading it so my memory could be wrong.

So they use sunlight and moonlight?

 

[A_Blind_Reefer]

Is your Cheato even growing? Looks like there is one only fish in the tank. If so, nitrate and phosphate is going to remain low with so little organic input, even without the Cheato. I don't know what your fuge consists of, but it may not really be doing much at the moment. What N & P are developed by the one fish and a little from decomposition of uneaten food is probably handled by the rock right now via denitrification and binding of the phosphate. This will change as you add more fish to the tank and the bound phosphate level rises on the surfaces of the rock.

And... Just my opinion... All is well as long as there is some detectible N&P. Within reason, the number doesn't matter. I would not do anything as long as the nutrient level trend is not rising. Your tank is only 3 months old. Nutrient levels will start rising soon enough.

+1 for this. My personal opinion, just that, an opinion is that starting a tank with a fuge is counter productive. It strips everything from the system when there’s really nothing to spare in the beginning…. Unless it’s fully stocked with fish. I know I’ll get kickback on that, but that is my experience.

 

[GARRIGA]

So they use sunlight and moonlight?

No. They take up nutrients at all hours but that efficiency is dependent on nutrient as to during or absent of light. Photosynthesis requires light which converts sugars to energy as I recall it.

Point being that during the night it’s still drawing nutrients but light affects to what level based on my recollection.

Really good reading that might apply to refugiums on some level.

 

[Lavey29]

+1 for this. My personal opinion, just that, an opinion is that starting a tank with a fuge is counter productive. It strips everything from the system when there’s really nothing to spare in the beginning…. Unless it’s fully stocked with fish. I know I’ll get kickback on that, but that is my experience.

I agree with this also.

 

[A_Blind_Reefer]

I agree with this also.

I never really understood adding nitrate and phosphate, or branded chaeto grow stuff, into a new tank with zero bio load. Especially for novices! Animals and food is so much easier. Algae is going to algae. Let it do its thing and have fish or critters go after it and get fat! Another opinion…. Do not fall for the 1000 count clean up crew. Most will die and spike your nutrients making more algae. A few good men will do the job. Trochus, tuxedos and fish are great. Crabs, meh. Cool to watch

 

[ReefGeezer]

+1 for this. My personal opinion, just that, an opinion is that starting a tank with a fuge is counter productive. It strips everything from the system when there’s really nothing to spare in the beginning…. Unless it’s fully stocked with fish. I know I’ll get kickback on that, but that is my experience.

Having a small ball of Cheato in a fuge really does no harm at this point. It'll bind a little bit of nutrients but not a lot until there are enough to make it grow more rapidly... It is kind of self regulating in that respect.

The processing of organic input and the subsequent organic and inorganic nutrients is complicated, interconnected, and ever changing. When a tank is young, more help is needed to manage these inputs. The Cheato can provide that help.

There's some decent information in the article linked in my signature that talks about how these nutrients are used in interrelated processes.

 

[Lavey29]

I never really understood adding nitrate and phosphate, or branded chaeto grow stuff, into a new tank with zero bio load. Especially for novices! Animals and food is so much easier. Algae is going to algae. Let it do its thing and have fish or critters go after it and get fat! Another opinion…. Do not fall for the 1000 count clean up crew. Most will die and spike your nutrients making more algae. A few good men will do the job. Trochus, tuxedos and fish are great. Crabs, meh. Cool to watch

Yea I waited till about 8 months to add chaeto to my fuge but I did have to dose neophos and neonitro for couple months early on to keep things in balance while tank was fallow. Once I got a good bioload of fish things took over on their own.