figure this one out

i can not grow macros in my refugium, i have tried 3 times with all different types, but i can grow xenia. i have fancy dt worthy macros in my display tank all doing very well. but when i try to add some to the refugium they just denigrate and disappear . i upped the water threw the fug it was 300 gph now at 600 gph . I'm using a 6400k grow light over the fug. i now have red slime and another type of green coating algae and coralline growing in there with the xenia. these types of algae are not in dt my tank, just in the fug
i have rock coating the bottom of the fug and when i thin my xenia in my DT i throw it into the fug and it attaches to the rocks in there. i now have several rocks of xenia in there, that just keep multiplying. when i test i don't really see a color change as far as nitrates go , so they are very near 0 i haven't tested for phosphate in a while. so can't say what they are at this time. i even bought another test kit for the nitrates to double check this reading. since i was shocked by it. and figure with all my fish that couldn't be so.
why won't macros grow in there! like cheato, but they will grow in the DT. i have tested the cheato in the dt and it will grow, than put it in the fug and, it disappears

 

i had the same issue. All my chaeto just died in my refuge. But red slime grows? idk its weird.

 

If it grows in your display, then what is different in your display?

- The water has to be the same, so, there has to be nutrients/trace elements.

- Presumably the temperature is the same.

So, what is different?

Flow?

Lights?

Where in the display does it grow? Is there high/low flow/light? What is the spectrum of light in the display?

 

macros use the phosphate in the water to grow so if your phosphate is really, really low, you'll have trouble trying to grow them.
how old your're light is and flow will also effect growth

 

my display is running a 1800mag as its only flow, and thats throttled back a bit to about 1500 ??? I'm guessing.
my light on the display is a ecotech radion, set at natural mode. which mimics daylight. gradual up and down in lighting.

here is what I'm wondering. Ive been feeding the fug with my uv lights out water and now with my reactors out water. i can't see this making that big of a deal. there should still be nitrates to feed algae. shouldn't there?
and if xenia grows why won't macro algae? it makes no sense to me.

 

Probably due to the shift in light spectrum from your dt to your fuge.
You said your fuge is 6500k, what is your dt?

 

if you figure it out let me know!

guess i better test the phosphates, but the tanks macros grow. i did think of the bulb and changed it with no change in results. how much flow is needed in a fug,, what do you run threw yours?? this is something i also was thinking and upped the flow from 300gph to 600 gph

 

You should be able to get this from the Radion software.

My guess though is that another good hint is the cyano. The cyano may like the yellow light more than the chaeto also, it tends not to like flow. As it isn't in your display, you likely have less yellow light and more flow in your display.

Perhaps the cyano is even smothering the chaeto out. Or even cyano toxins. Cyano may produce toxins, but these are destroyed quickly by intense light. If your light is dim, in the fuge, this may not happen. Not sure if they would effect chaeto though. Anyways, regardles, I'm guessing your Radion is set "bluer" and more intense than the fuge light. Trying more intense, bluer light may not be a bad idea and maybe add a powerhead to the fuge.

 

from what i under stand my radion is set at what would be close to 14k

 

My money is on the light source.