Nitrates stuck at 15 ppm for half a year, now suddenly 2 ppm after 2 days blackout

daggerana

New member
Picture of tank: https://ibb.co/DWG6Jcp


Only read last sentence for TL;DR.

I'll try my very hardest not to make this a wall of text... but as I found out as I was writing this, it turned out to be one after all. If any info is missing, tell me and I'll edit and/or comment.

Info on tank will be further down.

I'll start out with my algae problem has been adressed by maybe 50 people on other sites and forums and long story short I will be trying ROWA and water changes and biopellets and skimmer later down the line if I can not get rid of my algae problems with more natural and simpler means. Also I know about NoxPhox or whatever and other phospate binding solutions, and know about carbon dosing. I am currently thinking about which route I want to try down the line, but I am not gonna try everything at once, and will take my sweet time deciding and trying.

Currently only gonna try with the following: 3 day blackout, and an algae scrubber running on 18 hours light during the entire blackout. Will be trying the algae scrubber for some months onward probably, then I'll probably go with a skimmer if no results, most likely.



But back to my question! Why have my nitrates suddenly decided to break free from my 6 months continuous 15 ppm golden number and dived down to 2 ppm? First time since day 1 of the tank nitrates have been this low.

Only thing I have done recently was add some small amounts of aminos some weeks ago, and I made an algea scrubber 3 weeks ago. Added 2x Lionfish 2 weeks ago.

2 days ago I blacked out my tank with big black trash bags. Then, one day later, took a nitrate reading, and it showed 6 ppm. Then, earlier today, took a new reading, and it showed 4-5 ppm. And took one some hours ago, and it showed 3 ppm.

I am completely baffled, as I thought algae dying from no light would mean insanely high nitrates, because as you can clearly see in my picture, I have alot of algae. Is this all just a calm before the storm? Will my nitrates be in the 300ish tommorow?

As I said earlier, I have had my nitrates stuck at 15 ppm for like 6 months, never going up or down. Algea growing at insane speeds, not seeming to stop or slow down. Every SPS I added dying within days/weeks, LPS somehow unaffacted, but slow growth.



Info on tank:540 liters, or like about 140 gallons-ishhh.

Don't have a phospate reader yet, getting it soon.

Started with only dead rocks, added a few pieces of live rock from various sources to seed. Things I have noticed is Vermetid snail, other snails, bristleworms, bristle star fish, small shore-shrimp-like things, and I think I might have a mantis/pistol shrimp somewhere because god awful annoying frigging clicking noises sometimes. Have not seen it yet, might be snails or hermits playing tricks on me. Don't know. Maybe something else. Some tiny sponges aswell.

Only first started feeding for the first time, two weeks ago with the Lionfish, feedin' em shrimp tails once a week (yay started eating dead food really early ((also please tips on what else I can feed the Lionfish that is readily available, don't have a reef shop in like a 5 hour radius around me, and I know shrimp is bad for Lionfish but I don't have anything else atm)). I'll say it again, NO FEEDING for almost a year. Nothing.

TDS readings, 45 ppm from the tap, 12 ppm after RO filter. Getting new filters as soon as I have the money.

Stock is 1x Blue tang, 2x Lionfish, tiny CUC consisting of 4 snails and 4 Kenya mix hermit crabs.

Skimmerless, sumpless, no water changes. Only have algae scrubber on the right side of picture, installed 3 weeks ago.

Been running for about a year, 90% of that time a Blue Tang has been in it after it was cycled ofc, and 2x Lionfish was added 2 weeks ago.

Maxspect 420R. Lights on for 12 hours at 80/80. Always moonlight at night. I have had my lights at 30/30 for the majority of the time, long story short in an attempt to save SPS bleaching and stopping algae growth but of course it was a stupid idea and did nothing. Learned my lesson. After upping to 80/80 slowly, colors are returning to my corals and everything has looked ALOT better. Funny little example is my Kenya tree was blue when I got it, and glowed under blue lights. Then it turned pink and stopped glowing, probably because of 30/30 light. Turned up lights to 80/80, started turning blue, and glowing again. Also have some Kenya's that are at the top of rocks, and I think they are even starting turning green, and glowing ALOT in blue light?

Water values are normal +10-20% more. Temp 24c, Ph 8.2. Some values higher because I f'ed up recently adding too much, and I don't have much corals using Ca and KH so values are slooowly getting lower. Have been testing for Ca, KH, Mg, No3. Mg above 1500, and have always been high for some reason (by the way, any tips on maybe lowering Mg alone without affecting anything else?). My phone died recently along with my records, so can't tell exact numbers. I suppose I could take some tests right now if exact numbers are needed.

I am using Red Sea's Foundation Skeletal Elements powder to keep Ca, KH, Mg and trace elements up. Seperate Ca dosing powder if Ca is getting low, dosing Sodium Bicarbonate if KH is low. Please comment if this stuff is horrible and I should stop using it.

Not dosing or adding anything mysterious to the tank. Added tiny amounts of amino stuff some months ago, noticed brown algea (dino???) started appearing around then.

_______________________

TL;DR: 15 ppm nitrates for 6 months straight, blackout for 2 days, nitrates now 2 ppm. Why?
 
[welcome]

I am not sure at all. Maybe the die-off from the blackout has encouraged growth in the algae scrubber, but that's only a guess.
 
Thanks alot for the welcome!

Yeah, although I have peeked into my algae scrubber, and it's... if I have to put in in percentages, it's like 5-10% "full"? So I'm still clueless... Maybe I have a new type of super algae that does not require light to grow or something, hahah!

On the third and final day of the blackout, nitrates are now 3 ppm, measured in the morning. Taking another nitrate measurement later today, and taking off the black trash bags, exited to see how it turned out!
 
Not dosing or adding anything mysterious to the tank. Added tiny amounts of amino stuff some months ago, noticed brown algea (dino???) started appearing around then.

Typo here, added small amounts of amino stuff some WEEKS ago, and noticed brown algae**
 
Final day of blackout, time to see the results.

Picture: https://ibb.co/rMjNjRp

Dissapointed to say the least... I suspect my algae scrubber leaked too much light to be a complete blackout...

So what did change? Well, the blackout killed almost all of the brown algae, so that's a plus. The green algae, not so much... You can't tell in the picture, but the algae does look horrible now, like it has died, not lush and "pretty" like it was before.

But well my nitrates are amazing at 3 ppm, for some reason... that's good, right?

Will now be doing 4 hours of light a day, 80/80 strength, no moonlight in between. Waiting for my rapidleds to arrive so I can switch out the led strip in the algae scrubber. And about that, there is no change in the amount on it. There's almost nothing, except for a few strands of hair, but it is completely green with a green film. Also in the middle there is a brown film now... The starting of cyano maybe? Dino? I have no clue. Too early to tell. maybe it's just some slime, can't tell at the moment.

So this blackout achieved some things, which is heavy death of my brown hair algae (dino?), nitrates have dived to 3 ppm, and I upset alot of corals... I had some pieces of green trumpet's I managed to salvage from an algae attack on the mother coral, but a majority of them have died in the blackout, although 3-4 pieces are still live and well.

I wonder what I will do now... another blackout, but no algae scrubber running this time? Do I just continue with the blackout now, or do I wait? I wonder if the nitrates will stay low... Any suggestions?
 
Blackouts tend to work well for photosynthetic microbes. Larger algae often can survive quite a while without light, so I wouldn't expect a few days to kill hair algae, for example. The brown film that's shown up probably is microbes, maybe cyanobacteria or dinoflagellates, feeding on the nutrients released by the die-off. A few large (15-20%) water changes might help some, but it's hard to be sure. Remember that your kit only measures nutrients that have been mineralized, that is, decayed fully.

I think the lowered nutrient level is good. If it weren't for the lion fish, I'd probably try spending a few minutes a week harvesting any large, easy-to-get chunks of algae, to try to export nutrients, but I wouldn't put a lot of effort into it. I'd probably stop feeding for a week or two.

What is the flow rate to the algae scrubber?
 
Yeah.

The lionfish and the bristleworms keep me from getting too comfy putting my hand in the tank.

7 liters of air per minute or something, an Eheim double air pump.
 
HOG algae scrubbers (hang on glass) ain't got no water pumps, so I don't know that. However it is right next to a circulation pump
 
Algae growth

Algae growth

Why the algae grow very fast?
The growth rate depends off the nitrogen source used. Algae prefer ammonia-nitrogen as a nitrogen source and may grow 8x faster using ammonia instead of nitrate.
Limiting the ammonia-nitrogen availability will slow down the algae growth.
This can be done by fast heterotrophic growth ( vodka) or increasing the nitrification and denitrification capacity. Adding vodka will also limit the availability of the other building materials needed for algae growth. The disadvantage of vodka dosing is that one must continue dosing. Installing a high CN ratio will not only limit algae growth but also remove the installed nitrification capacity as heterotrophs will win the battle for available ammonia-nitrogen. it is a choice to make.
Blackouts will reduce the algae but will not remove the cause. it will increase the problem as less ammonia will be taken up.
Nitrate went down! What about the presence ammonia?

As in this tank, a lot of ammonia may be produced due to the presence of 2 meat lovers an effective ammonia reduction capacity must be in place. Removing Photo-autotrophic growth without replacing it may introduce a bigger problem as algae growth will ever be.
 
Just got some testing done and finally with phospate

Salinity 1.026
Ca 470
Alk 9.0 dKH
Mg 1500
Ammonia 0
Nitrite 0
Nitrate 5
Hannah Phospate tester: 0.04 ppm

About the phospate test, problem is the Hannah tester has an accuracy of 0.04 and +/- 4% or something something along those lines, point is my reading is within the accuracy range, which means that my phospate is anywhere from 0.00 and 0.08, in theory.

So all my values are now more or less ideal.

Algae scrubber is in the early stages of growing various stuff, including but not limited to brown/orange goey stuff, dark green/light green algae, showing decent growth, lights are now upgraded to 4x photo red and 2x royal blue leds from RapidLed. And air flow is now fixed as previously it was just some lousy holes in the tubing, now using the air thingies that came with the Eheim air pump, and man those things can bubble!

I'm starting to think my algae problem is just because too few corals consuming nutrients and WAY too little of a clean up crew... And that's it. Time to up both of them, I guess, and see where it goes!
 
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