Chaeto questions

Charles Belisle · Sep 16, 2020

Recently I have notice that parts of my Chaeto is showing signs of turning white. It is not in patches or one centralized locations; but more like separate roots (looks like an old man's white hair). The main piece is still dark green; with these white hair like roots. My phosphates have been around .5 (using API testing) with nitrates 0.0. Everything in tank has been looking good; have zoas, torch, and hammer corals; so a little dirty water is good. I am seeing very small patches of new GHA growth here and there; but nothing that my Lawnmower blenny will not be happy to take care of. I have a ACKE LED Grow Lights Full Spectrum,Plant Lights，Growing Lamps 12W for Indoor Plants,Hydropoincs (Red Grow light). That sits about 8" above the refugium; which I run about 12 hours. I have 2 different sets of Chaeto; one that sinks (big ball about the size of 2 softballs) and 3 smaller - fist size that seem to float. The 3 floating pieces; seems to grow a green moss on the top where it sticks out of the water. (I try to flip these offen to reduce the gree moss growth).

Questions are: what is driving the white hair like roots? (these are not worms - they don't move). Why does one chaeto float and the other one doesn't? Is the green moss need to be removed?

Additional information - I had good Copepods population; until my Strip Blenny took a ride down to the sump - and into the refugium. Returned him to main tank last night. When I added the Copepods to the refugium; I cut the flow from the refugium for fear of washing them into my main. Will slow flow through the refugium have an affect on the Chaeto? It has been in refugium for about 3 months now; and I have not trimmed it as of yet (not a lot of growth) because I have a lot of room for new growth; before I need to start harvesting.

Should I reduce lighting length? Increase flow? Harvest? Add a Chaeto grow?

Thanks for any help.

ThePurple12 · Sep 16, 2020

That would be the nitrate level of 0. Macroalgae need nitrate to grow, and since the Chaeto doesn’t have it, it’s dying.

The green moss could be some kind of hair algae, and it’s producing oxygen with growth, causing the chaeto to float.

I‘m not sure if the flow matters or not with macroalgae.

Charles Belisle · Sep 16, 2020

Okay - solution to Nitrate - is to feed everyday; been skipping a few days throughout the week and to reduce skimmer operation by 6 hours daily. While monitoring Nitrate levels.

For floating Chaeto - a guess a good scrub and then to place it below the main chaeto ball out of direct lighting. Hopefully this will kill off any bad algae and reduce its desire to float...

Thanks for Help.

ThePurple12 · Sep 16, 2020

Healthy chaeto will float anyway because it's producing oxygen. Good luck!

sfin52 · Sep 16, 2020

If you are bottoming out nutriends cut the light back. Instead of running 12 hours try 8.

If the cheato is melting watch closely. If it all melts it will release all the nutrients and anything else it absorbed back into the tank.

rkpetersen · Sep 16, 2020

Chaeto can be finicky in a refugium, more so than many other macroalgaes, such as ulva.

If your chaeto is healthy and growing, it will float, be covered in oxygen bubbles, and rapidly start to fill the space it's in.
If it's not doing well, it will sink, fragment, and/or turn white. If it starts to fail like this, it's important that the dying chaeto and maybe even the whole batch be removed immediately. Otherwise you are rapidly dumping nutrients back into the water, and the benefit accrued while that chaeto was growing will be lost.

There needs to be some nitrate and phosphate in the water. Not a lot, but not zero. Part of the trick with chaeto is keeping just enough in your fuge to absorb nutrients generated by the display tank animals, but not so much chaeto that it drives the nutrient levels to zero and then dies back itself. To accomplish this you need to test frequently and develop a good sense of how much chaeto is enough but not too much for your particular system.

Trace elements can be important for chaeto. Supplementing iron is frequently recommended and I do so myself. Other deficiencies can also have an effect on chaeto, such as molybdenum, but these are less clear factors and difficult to assess accurately.

Flow is also important for chaeto. I put rocks under my chaeto, which keeps the algae near the water surface and also forces more water flow through the algae rather than under or around it. Before I added the rocks, flow was slower and chaeto would sometimes start to fail, but with higher flow, it grows vigorously.

Also, you want your pods to flush from the fuge to the display. That's one of the main purposes of having a fuge - providing a steady supply of food organisms for the animals in the display tank.

AlgaeBarn · Sep 16, 2020

Do you have any pictures? ~Shaun K

Charles Belisle · Sep 17, 2020

rkpetersen said:
Chaeto can be finicky in a refugium, more so than many other macroalgaes, such as ulva.

If your chaeto is healthy and growing, it will float, be covered in oxygen bubbles, and rapidly start to fill the space it's in.
If it's not doing well, it will sink, fragment, and/or turn white. If it starts to fail like this, it's important that the dying chaeto and maybe even the whole batch be removed immediately. Otherwise you are rapidly dumping nutrients back into the water, and the benefit accrued while that chaeto was growing will be lost.

There needs to be some nitrate and phosphate in the water. Not a lot, but not zero. Part of the trick with chaeto is keeping just enough in your fuge to absorb nutrients generated by the display tank animals, but not so much chaeto that it drives the nutrient levels to zero and then dies back itself. To accomplish this you need to test frequently and develop a good sense of how much chaeto is enough but not too much for your particular system.

Trace elements can be important for chaeto. Supplementing iron is frequently recommended and I do so myself. Other deficiencies can also have an effect on chaeto, such as molybdenum, but these are less clear factors and difficult to assess accurately.

Flow is also important for chaeto. I put rocks under my chaeto, which keeps the algae near the water surface and also forces more water flow through the algae rather than under or around it. Before I added the rocks, flow was slower and chaeto would sometimes start to fail, but with higher flow, it grows vigorously.

Also, you want your pods to flush from the fuge to the display. That's one of the main purposes of having a fuge - providing a steady supply of food organisms for the animals in the display tank.

Thanks for the in-depth write up.