Algae in CO2 aquarium after Easy Green

[alehuta]

Hey guys, I have a tank with moderate to heavy plants and CO2 injection. I recently decided to try Easy Green in place of my Fluorish because I had heard so much good about it. At the next dose of Fluorish I began dosing Easy Green. I am now about 3 weeks in and what looks to be black beard algae is starting to go crazy. No other changes have been made other than changing the brand of fertilizer. 

65 gallon tank (36x18x24). pH is 7.2-7.4.  0 ammonia, 0 nitrite, 20ish nitrates, and phosphates are about 0.75ppm. (It hovers arpund these values even without water changes).   CO2 injected about 3.5 bubbles per second, dosing 6ml of Easy Green 2x a week (same as was done with flurorish). Light is a Fluval Plant 3.0, run at the OEM 100% values for 7 hours plus ramp up and down time - yes I know thats a bit more than recommend in most cases but it worked well with other ferts, and bear in mind it's a deeper-than-typical tank.

 

Any ideas here? I'm guessing the Easy Green had a hand in it since it started after switching to it. But as far as balance goes, any ideas for more CO2, less light, less fertilizer, combination thereof? Never had an issue with black algae before and I'm wanting to take care of it before it overruns the tank. I know the blackout thing to help kill lit off, or removing effected plants etc. But as far as treating the root cause, any ideas based on info given?

[Mmiller2001]

Seriously low PO4, and looking like Fe is low as well.

[alehuta]

On 8/30/2024 at 4:26 PM, Mmiller2001 said:

Seriously low PO4, and looking like Fe is low as well.

Okay, I actually just started testing phosphate because of the algae beginning. I saw a bunch of mixed information but most seemed to indicate 0.1 to 0.5ppm being favorable for freshwater. What SHOULD it be at since what I was reading before sounds to be incorrect? 

 

Guess I better pull those phosphate pads I got back out of the filter 😂

[Mmiller2001]

I run my tank’s between 8 and 10ppm. Move up to at least 4ppm. If you see green spot algae, raise it to 8ppm. 

[alehuta]

On 8/30/2024 at 4:34 PM, Mmiller2001 said:

I run my tank’s between 8 and 10ppm. Move up to at least 4ppm. If you see green spot algae, raise it to 8ppm. 

Any recommendations on a phosphate additive? I haven't looked at the nutrients in Fluorish but I'm guessing it contains phosphates, at least much more than Easy Green and that's where the deficiency and algae are coming from

[Mmiller2001]

Flourish is not a complete fertilizer, it’s just micros and extremely low amounts of macros. It’s barely a supplement. 
 

I would just get a pound of KH2PO4 from Green Leaf Aquariums and just dry dose it.

[Beach Cruiser]

On 8/30/2024 at 4:34 PM, Mmiller2001 said:

I run my tank’s between 8 and 10ppm. Move up to at least 4ppm. If you see green spot algae, raise it to 8ppm. 

Interesting! @Mmiller2001

I don't run CO2 in my heavily planted tank & have recently been getting a bit more GSA than I like (pretty much Anubias leaves exclusively). My usual phosphate level reads 1-2ppm dry dosing KH2PO4. 

What level would you recommend for medium light/low tech? 

Thanks!

[alehuta]

On 8/30/2024 at 10:20 PM, Beach Cruiser said:

Interesting! @Mmiller2001

I don't run CO2 in my heavily planted tank & have recently been getting a bit more GSA than I like (pretty much Anubias leaves exclusively). My usual phosphate level reads 1-2ppm dry dosing KH2PO4. 

What level would you recommend for medium light/low tech? 

Thanks!

Never done any dry dosing here. I see it's KH2PO4, but where do you recommended to get it?  And how does dosing go for it?

[Beach Cruiser]

On 8/30/2024 at 10:37 PM, alehuta said:

Never done any dry dosing here. I see it's KH2PO4, but where do you recommended to get it?  And how does dosing go for it?

It's super easy/cheap.  Several online suppliers like the one mentioned above sell various dry "salts" that are used for fertilizer. Basically they're different powders that you measure small amounts & add to aquarium water (i usually add mine to a pint or two & pour back into the tank). Most are like $4 for a couple years worth. You'll also need small measuring spoons that go down to 1/8 - 1/4 teaspoon. Plastic ones only cost a few bucks. 

There are online calculators (i use rotala butterfly) that allow you to enter tank size, nutrient & concentration you want (ppm) and it will tell you how much to add. 

For instance it says: for a 65 gallon tank, you'd add 1/4 tsp to reach 4ppm of PO4. After that, I just calculate for water change volume each week & test every once in a while to be sure I'm on track.

[Mmiller2001]

On 8/30/2024 at 8:20 PM, Beach Cruiser said:

Interesting! @Mmiller2001

I don't run CO2 in my heavily planted tank & have recently been getting a bit more GSA than I like (pretty much Anubias leaves exclusively). My usual phosphate level reads 1-2ppm dry dosing KH2PO4. 

What level would you recommend for medium light/low tech? 

Thanks!

4 to 5 but try 3 first.