Chaeto slowdown with normal water parameters

[RajV]

Over the past 10 days my Chaeto is shrinking in volume . I had a nice growth that was fluffy light and distributed by volume in my entire sump area it belonged , its now shrinking and heavy and is almost 25 % of the space it occupied. It is not dying.

What could be the reason ?

My Ph is stable 8.2 to 8.1 swing
My Ammonia is constant .007
Nitates 0
Alk 8
Calcium 413
Mag 1299
Phosphate .2

Lighting MaxGrow adjustable Led

Any pointers to reviving its growth is greatly appreciated

 

[Dr. Dendrostein]

Maybe, not enough nitrates, phosphates to consume?

 

[Kayvon]

I'm having the same issue. Got a Triton test, and it said I had low Potassium.

 

[RajV]

Maybe, not enough nitrates, phosphates to consume?

is that coming from the feed and waste ? then that has not changed also

 

[Caravanshaka]

you want to get your nitrates detectable, more like 1-4 ppm. Chaeto needs that and phosphate to thrive.

 

[RajV]

I'm having the same issue. Got a Triton test, and it said I had low Potassium.

My potassium is at 330 on a target of 380 - my thinking is that number isnt point to the problem

 

[Dawsokj1988]

That's some really low potassium! I thought 400 was the target.

 

[RajV]

That's some really low potassium! I thought 400 was the target.

I understand , bit is that directly related to the degrowth

 

[teller]

you want to get your nitrates detectable, more like 1-4 ppm. Chaeto needs that and phosphate to thrive.

Unfortunately things with macro algae are not so nitrate/phosphate only.
If you see a site like :
https://www.marineplantbook.com/marinebookpage10.htm
There are more macro and trace elements involved.
For some reason Triton has a line specific with additional traces dosing.
Pax bellum Arid also has additional bottles of traces to add like iron and manganese.
Etc... That is the reason some people eventually fail in macro algae.
I do not say everyone has to supplement. As I said before, I belive that if you consistently add nori for your fish probably you do not have to dose iron.
In my case I have a nano and so I don't add nori, so I dose iron.

 

[Randy Holmes-Farley Verified Community Expert]

I'd raise the potassium regardless of any other issues. It may or may not slow the growth of macroalgae.

It may "need" more nitrate to grow more, but whether you dose it to drive that growth is up to you.

I do think that iron and some other trace elements (e.g., manganese) are needed, rapidly depleted, and easy to dose.

 

[RajV]

I'd raise the potassium regardless of any other issues. It may or may not slow the growth of macroalgae.

It may "need" more nitrate to grow more, but whether you dose it to drive that growth is up to you.

I do think that iron and some other trace elements (e.g., manganese) are needed, rapidly depleted, and easy to dose.

I must confess , i had this hope of getting a response from you .. thank you , love reading your chemistry articles that demystify and makes this hobby easier . What would be the best supplement to increase pottasium ? @Randy Holmes-Farley

 

[Randy Holmes-Farley Verified Community Expert]

Thanks.

i'd use a potassium chloride product, such as this DIY:

https://www.iherb.com/pr/Now-Foods-Potassium-Chloride-Powder-8-oz-227-g/777

 

[tigé21v]

What's the difference between potassium chloride and potassium sulfate? Would there be any benefit from mixing the two (like Brightwell Aquatics does)?

 

[Randy Holmes-Farley Verified Community Expert]

What's the difference between potassium chloride and potassium sulfate? Would there be any benefit from mixing the two (like Brightwell Aquatics does)?

IMO, there's no real benefit since the amounts are too low to matter to the chloride/sulfate balance. Either just KCl, or KCl plus a little K2SO4 (maybe 10:1) would be my pick.

 

[RajV]

Update
SO from some of the replies here and from what I have understood and this statement from @Randy Holmes-Farley from a different thread "All this really says is that given too little light, the algae will slowly shrink and disappear (and die)", I decided to test the refugium light under a par meter from @AQD-Seneye . So the light was putting out approx 3K (kelvin) - no big issue on the spectrum that was a surprise . I pushed that back to 6K . Im not sure if i inadvertently hit the knob or has the led lost power - or the driver has gone weak - or may be the controler's resistance has gone goofy . Its now 4 days since i made the change and I find it growing back . There something I missed - There was a clear indication from May 2nd , my Seneye was clearly showing that the pH was not increasing at night when the refugium goes on and it also points back to the 3 weeks of me seeing the slow degrowth . I can now see the pH raise every night as well after the change to the lighting . Thanks all for pitching in here