# How do people keep lights on for long time and avoid algea?



## sagarjoshi (Jun 10, 2017)

I have 32g biocube. My filter also has denitrifying bacteria, so I always have 0 ammonia, nitrites and nitrates.

I wouldn’t say my tank is densely planted but it’s moderate. I have anubias, Java moss and dwarf baby tears in my tank. I keep lights on for about 6 hours and start getting algea by end of two weeks.

Is it possible to keep lights on for longer time and keep algea off?


Sent from my iPhone using Tapatalk


----------



## tamsin (Jan 12, 2011)

Floating plants, they cut out some of the light below but still leave enough to light the tank. You could also dim the light in some way e.g. move it farther away, frost the top glass etc.


----------



## hivemindhermit (Oct 19, 2017)

Another option is to split the photoperiod. Keep the lights on for a few hours in the morning and evening, leaving them off mid-day (or whenever you're usually not by the tank). 

Sent from my Pixel using Tapatalk


----------



## Kubla (Jan 5, 2014)

Zero nitrates with plants is a problem.


----------



## sagarjoshi (Jun 10, 2017)

Kubla said:


> Zero nitrates with plants is a problem.




Can you elaborate?


Sent from my iPhone using Tapatalk


----------



## Quagulator (May 4, 2015)

sagarjoshi said:


> Can you elaborate?
> 
> 
> Sent from my iPhone using Tapatalk


Macro nutrients are used in large quantities by plants. They include nitrogen, phosphorous and potassium. Plant available forms of Nitrogen are ammonia (bad for our tanks, and always at 0 in a cycled tank) leaving nitrate nitrogen as the main source for plants. so having nitrates in the tank means it is not the limiting factor in your plants ability to perform its daily functions.


----------



## jellopuddinpop (Dec 12, 2016)

sagarjoshi said:


> Can you elaborate?
> 
> 
> Sent from my iPhone using Tapatalk


Plants need Nitrate to grow. Most keep their Nitrate levels between 10 and 20 ppm.


----------



## sagarjoshi (Jun 10, 2017)

Sine I have denitrifying bacteria there are no nitrates. Do I need to supply nitrogen in form of fertilizer?


Sent from my iPhone using Tapatalk


----------



## Quagulator (May 4, 2015)

sagarjoshi said:


> Sine I have denitrifying bacteria there are no nitrates. Do I need to supply nitrogen in form of fertilizer?
> 
> 
> Sent from my iPhone using Tapatalk


Nitrogen is a highly mobile nutrient and does not bind to soil particles very well. If you add fertilizer microbes will utilize the nitrogen and release it as ammonia (which is converted to nitrate) or as nitrate which will be utilized by your denitrifying bacteria. 

What is your source of the denitrifying bacteria? Usually they exist in extremely low oxygen environments, and operate anaerobically.


----------



## IntotheWRX (May 13, 2016)

sagarjoshi said:


> I have 32g biocube. My filter also has denitrifying bacteria, so I always have 0 ammonia, nitrites and nitrates.
> 
> I wouldn’t say my tank is densely planted but it’s moderate. I have anubias, Java moss and dwarf baby tears in my tank. I keep lights on for about 6 hours and start getting algea by end of two weeks.
> 
> ...


the plants you have are low light plants. they dont need much lights to do well. 

adjust the lights to your plants/tank. if you try to force your tank to high light then the algae will win.


----------



## Kubla (Jan 5, 2014)

Dwarf baby tears, Hemianthus callitrichoides, is not a low light plant. I don't have any experience with it but most list it as a high light plant. 

In order to get any kind of educated advice you're going to have to give more info about your situation. What kind of algae are you dealing with? What lights are you using? What kind of circulation/filtration do you have in the tank? What kind of nutrition are you providing for the plants? CO2? Excel? You can't hardly give too much info. Water temp, KH, GH, PH, substrate type, fish load, water change % and frequency and the age of the setup are good to know too.

With zero nitrates you aren't providing proper nutrition for your plants or algae. Unfortunately, algae will outperform plants when conditions are poor.


----------



## KayakJimW (Aug 12, 2016)

sagarjoshi said:


> Sine I have denitrifying bacteria there are no nitrates. Do I need to supply nitrogen in form of fertilizer?


Nitrates are actually the waste product of the bacteria. They turn Nitrites into Nitrates. Water changes and plants remove Nitrates.

To super simplify things: having some Nitrates will allow the more advanced plants to thrive and outcompete the lesser advanced algae and starve it. With what you have, I would look into an "all in one" fert like one of @nilocg's Thrive fertilizers and start with about a half dose and ease into it


----------



## hivemindhermit (Oct 19, 2017)

sagarjoshi said:


> Sine I have denitrifying bacteria there are no nitrates. Do I need to supply nitrogen in form of fertilizer?
> 
> 
> Sent from my iPhone using Tapatalk


You mean you have nitrifying bacteria. The bacteria turn ammonia into nitrites into nitrates, which are then removed by your plants. Denitrifying bacteria is a different thing altogether  These terms are super confusing though, I know! 

Sent from my Pixel using Tapatalk


----------



## Quagulator (May 4, 2015)

hivemindhermit said:


> You mean you have nitrifying bacteria. The bacteria turn ammonia into nitrites into nitrates, which are then removed by your plants. Denitrifying bacteria is a different thing altogether  These terms are super confusing though, I know!
> 
> Sent from my Pixel using Tapatalk




I think op meant denitrifying bacteria. They consume nitrogen and release is as N2 gas in anaerobic conditions. There are filters made for this, extremely slow water flow promotes anaerobic conditions where these bacteria can live, consuming nitrate N and releasing it as harmless N2 gas. 


Sent from my iPhone using Tapatalk


----------



## Darkblade48 (Jan 4, 2008)

Quagulator said:


> I think op meant denitrifying bacteria. They consume nitrogen and release is as N2 gas in anaerobic conditions. There are filters made for this, extremely slow water flow promotes anaerobic conditions where these bacteria can live, consuming nitrate N and releasing it as harmless N2 gas.
> 
> 
> Sent from my iPhone using Tapatalk


I too, would be very skeptical that there is a source of denitrifying bacteria in a typical aquarium setup (without a plenum).


----------



## sagarjoshi (Jun 10, 2017)

I do have nitrifying and denitrifying bacteria.


Sent from my iPhone using Tapatalk

At this point I cannot replace the plants I have with plants requiring high light. I guess I will start with very low dose of fert and see how it goes??


Sent from my iPhone using Tapatalk


----------



## hivemindhermit (Oct 19, 2017)

Quagulator said:


> I think op meant denitrifying bacteria. They consume nitrogen and release is as N2 gas in anaerobic conditions. There are filters made for this, extremely slow water flow promotes anaerobic conditions where these bacteria can live, consuming nitrate N and releasing it as harmless N2 gas.


Fair enough, and OP has confirmed as well. It's my experience that people get the terms mixed up. Sorry for assuming!


----------



## Quagulator (May 4, 2015)

hivemindhermit said:


> Fair enough, and OP has confirmed as well. It's my experience that people get the terms mixed up. Sorry for assuming!


It's all good, I went to school learning about nutrient management and know the terms well that's all. I still get some mixed up. OP you can try and dose some KNO3 and watch nitrate levels to see if you can keep them above 0. I think the denitrifying bacteria you have wont be able to keep up to KNO3 dosing.


----------



## klibs (May 1, 2014)

balance plant mass (types of plants, density, etc are important) with light intensity and nutrients

you need to be a lot more specific if you want advice specific to your particular situation. post pics of your full tank, specify what equipment you use, what you are dosing, etc...


----------



## Quagulator (May 4, 2015)

klibs said:


> balance plant mass (types of plants, density, etc are important) with light intensity and nutrients
> 
> you need to be a lot more specific if you want advice specific to your particular situation. post pics of your full tank, specify what equipment you use, what you are dosing, etc...


There's no such thing as giving too much info for people trying to help OP. I agree, the more info the better we can try and find a solution.


----------

