kno3 dosing and algae blooming

[amir basis]

hi guys, would thank you for your thoughts and experience in the matter,

my 250 gallons reef tank has been running for almost 5 months now and its been doing pretty good overall.
the problem is that my corals growth have been really slow. in terms of making new crust over the rocks i did see a lot of progress there with my sps frags that became firmly attached to my rocks ,but in terms of new growing tips there have been barely any change or growth.
further more, in the last two months the colours became more and more pale. i realised that iv been running on too low nutrients (0 no3 and 0.05 po4) for a long time (i dose zeobac and use TLF biopelltes).
i have been dosing daily red sea reef enrgy amino acids but apparently its not enough, so i started dosing daily amount of kno3 that raises my no3 to 0.75 ppm per dose. i've noticed that by the next day it would drop back to 0 agin before the next dose.

i've been dosing for two weeks now and already my corals are showing colour improvement and polyps extension . the problem is that i also have a big outbreak of hairy like algae the is starting to cover all my tanks bottom and my rocks.
im afraid that it would eventually suffocate my corals.
what would you suggest me to do (beside maybe getting in some algae eaters)?

water parameters:
temp: 25 c
salinity: 1.026
ph:8.3
alk:8.9
cal:420
mag:1320
led lights, 9 hours a day (with sunrise and sunset)

thanks to all
:)

 

[NY_Caveman]

Is the algae green hair algae, or Cyanobacteria which is more of a red mat? Cerith or Turbo Snails may help green hair algae. Or hermits crabs. Curious though, did you try reducing or stopping the biopellets before dosing NO3?

 

[NY_Caveman]

By the way... Welcome to R2R!

 

[amir basis]

thanks for the welcome ;Shamefullyembarrased

the algae is a green one, its not cyano for sure.
i did try shutting off the biopellets but the problem is that my fish mass is pretty low (bunch off clownfish and one small blue tang) and they simply not producing enough no3. so it didnt help.

 

[NY_Caveman]

Right. I had the same reaction to dosing NO3 when I had 0 ppm. I stopped and the algae went away quickly with snail help. Maybe wean it slowly down and see what happens. I am no biopellets expert, maybe @Brew12 has thoughts as he seem to really understand how it can work well. For me I worry in a low bioload system it could strip nutrients (I say that knowing that is old news now).

 

[amir basis]

at what levels are you keeping your no3 now and how you do it?

 

[Brew12]

Thanks for the invite!

I've never used biopellets so I can't help much there. It sounds like you don't run a refugium or anything else along those lines? A healthy reef tank will grow algae since algae and coral have many of the same requirements. The trick is to get the algae to grow where you want it to or to have enough critters that eat it to keep it in check.
In your case, I think I would take the biopellets off line for now and add an algae turf scrubber unless your sump has room for a refugium. A chaeto reactor is also an option. Either way, a good size CuC will be of great benefit imo.

 

[Gareth elliott]

I would take the biopellet reactor offline or at least remove a good portion of the pellets. Say keep 1/3. And watch the results.

They are great for very heavy feeding systems where you start really high. In newer systems or systems that feed normally can outcompete corals for nutrients on the small bad at the very bad lead to a dino outbreak.

 

[amir basis]

thanks for your response!:)

as you probably realised i dont have a refugeume in my tank since my sump is too small for that and yes, my corals population isnt big enough yet to consume most of the nitarts instead of the algae.
i guess ill just try to get more algae eaters in the tank and maybe add more corals(shopping time ;Happy) to increase coral uptake of nutrients instead of algae.

 

[NY_Caveman]

Thanks for the invite!

I've never used biopellets so I can't help much there. It sounds like you don't run a refugium or anything else along those lines? A healthy reef tank will grow algae since algae and coral have many of the same requirements. The trick is to get the algae to grow where you want it to or to have enough critters that eat it to keep it in check.
In your case, I think I would take the biopellets off line for now and add an algae turf scrubber unless your sump has room for a refugium. A chaeto reactor is also an option. Either way, a good size CuC will be of great benefit imo.

Sorry Brew, for some reason I was thinking GFO. This is late in the day for me. LOL.

 

[NY_Caveman]

at what levels are you keeping your no3 now and how you do it?

I really do nothing and it stays around 2 ppm. I started with really rich live rock though that was cured and ready day one (I still matured the tank of course). I attribute that quite a bit to my system’s stability.

 

[SPR1968]

If you have green hair algae starting to grow, I would maybe suggest that it is using the added nitrate as a food source and also potentially giving a false low phosphate reading as that could also be used by the algae (I’ve been here myself).

As already said, you do need some nutrients for the corals to feed and it’s a balancing act. There aren’t many critters that effectively eat hair algae as far as I could find when I researched, especially when it’s the ‘long type’. Once under control and shorter, critters/fish may eat it.

What I did, was added Rhowaphos (GFO) in a reactor and locked the phosphate down very low (0.03ppm ish) and kept it very low by regular changes of the rhowaphos in the early stages. Over a period of weeks this removed all excess phosphate from the system, and starved the hair algae which eventually died off.

If you already reading 0.05ppm, then there isn’t much phosphate in anyway (other than possibly tied up in the algae/rockwork etc)so I don’t think it would have much affect on corals, but it will prevent any excess being taken up by the algae. Just monitor the system carefully and adjust as necessary.

If you want a quick fix, take a look at Vibrant liquid as well, but you need to sort the route cause out and take action to remedy it otherwise it will come back

Phosphate control is the single best thing I ever did in my system

 

[amir basis]

If you have green hair algae starting to grow, I would maybe suggest that it is using the added nitrate as a food source and also potentially giving a false low phosphate reading as that could also be used by the algae (I’ve been here myself).

As already said, you do need some nutrients for the corals to feed and it’s a balancing act. There aren’t many critters that effectively eat hair algae as far as I could find when I researched, especially when it’s the ‘long type’. Once under control and shorter, critters/fish may eat it.

What I did, was added Rhowaphos (GFO) in a reactor and locked the phosphate down very low (0.03ppm ish) and kept it very low by regular changes of the rhowaphos in the early stages. Over a period of weeks this removed all excess phosphate from the system, and starved the hair algae which eventually died off.

If you already reading 0.05ppm, then there isn’t much phosphate in anyway (other than possibly tied up in the algae/rockwork etc)so I don’t think it would have much affect on corals, but it will prevent any excess being taken up by the algae. Just monitor the system carefully and adjust as necessary.

If you want a quick fix, take a look at Vibrant liquid as well, but you need to sort the route cause out and take action to remedy it otherwise it will come back

Phosphate control is the single best thing I ever did in my system

thanks for sharing your excprience!:)

well when i started dosing kno3 my phosphate was higher than what it is now (much higher i would just cant remember how much exactly was it) and it definitely dropped down since i started dosing. i guess the algae consumed most of it (and i just removed most of the algae out of the tank two days ago). so just to make sure i understand you, if ill keep my po4 low and under control i might be able to keep that way my no3 high enough for the corals but without having to deal with massive algae outbreaks?

 

[SPR1968]

thanks for sharing your excprience!:)

well when i started dosing kno3 my phosphate was higher than what it is now (much higher i would just cant remember how much exactly was it) and it definitely dropped down since i started dosing. i guess the algae consumed most of it (and i just removed most of the algae out of the tank two days ago). so just to make sure i understand you, if ill keep my po4 low and under control i might be able to keep that way my no3 high enough for the corals but without having to deal with massive algae outbreaks?

Well that’s exactly what I do, phosphate is locked down to around 0.03ppm and nitrates are around 10-15ppm

My hair algae outbreak occurred when I was following the Red Sea Accelerated growth program which called for higher phosphate levels at around 0.1ppm. The algae grew slowly over a few months (I didn’t realise what it was at the time) from a dark covering to full blown hair algae when the phosphate hit around 0.16ppm. I tried Sea hares, crabs but nothing would touch it

Once I realised what was happening, I added rhowaphos. I had to change it regularly to start off as the excess phosphate was taken out of the system, but now I change it every 3-4 weeks and it keeps it under control.

Just keep an eye out on any corals, but I think you should be ok, otherwise slow the phosphate removal speed down by using less of whatever GFO you choose

 

[amir basis]

hey guys, al little update here,

my po4 levels has finally dropped down to 0.01-0 levels. i'm still dosing daily amount of kno3 to keep my nitrate levels on 1 ppm. i have noticed few changes regarding the coloration of the corals ,the algae bloom and overall water chemistry:

1-growing rate has significantly increased and the corals colours are much darker and strong, yet there still much room for improvement there (a matter of time and Patience i suppose).
2-my cal and alk are dropping way faster than before (i guess thats a good sign of increased growth)
3-the algae bloom has dramatically slowed down, yet there still a lot of brown hairy algae on the rock and walls of the aquarium. i'm thinking if i should just wait a bit longer for it to disappear or to use chemicals like vibrant?
4-the nitrate uptake is still very high. water testing shows 1ppm after dosing pump worked at 8:30 am, and by 14:30 pm the water test will show 0 again!. i'm a bit worry that these fast fluctuations will hurt the corals. would you recommend dosing more kno3 / extra few times during the day to keep a more constant values of no3? keep in mind that i still have algae on my rocks and not sure how the extra dosing of kno3 will impact that as well.

cheers all :)

 

[Sallstrom]

Hi :)
Keep an eye on the phosphate. When you are adding nitrate(which IMO is a good way to go), you are feeding the organisms taking up N and P(and other stuff). After some times the tanks might be stripped on phosphate. Specially when you are using a carbon source(bio pellets), this might go faster. With too low phosphate level your corals won't be happy and you risk getting Cyanobacteria.

About the algae I would recommend an urchin. Or two. I like the black long spined Diadema, but collector and tuxedo urchins are also great for grazing all kinds of algae.

Good luck!

 

[Skynyrd Fish]

This is where you need to observe the tank and decide if it is looking good or you want to tweak it. Sounds like you are in a sweet spot, or are really close. Post a pic.

 

[amir basis]

here are some pic of the corals and the algae i'm dealing with:

sorry if the images are a bit blurry, took it from my phone and the camera didn't like the blue spectrum that much.

but as you can see, the algae is everywhere:\

 

[Brew12]

here are some pic of the corals and the algae i'm dealing with:

sorry if the images are a bit blurry, took it from my phone and the camera didn't like the blue spectrum that much.

but as you can see, the algae is everywhere:\

Personally, I wouldn't dose KNO3 with that much algae in the tank. I would concentrate on getting algae eaters in the system. Once you get your algae under control your NO3 will climb naturally imo.

 

[amir basis]

the problem is im concerned that if i stop dosing kno3 my corals will start starving again and i dont konw if dosing amino acids would be enough for them-is my fear justified?

as for algae eaters- currently there aren't any available in stores in my area. as soon as they get i will introduce some to the tank.