Refugium hinders coral growth?

[VintageReefer]

I am not an expert in every type of macro algae or algae out there by any means but to make the broad statement refugiums / macroalgae prevent coral growth is a false statement. We would need some more detail/specifics.

I’ve used algae turf scrubbers for 11 years and refugiums for 10 years prior. There’s no issue with coral growth, at least none caused by chaeto or turf algae.

And I don’t do water changes or run a skimmer in either type of system, there is no build up of algae toxins impacting coral health.

 

[VintageReefer]

The assertion is that the algae is taking up vital nutrients faster than Coral can uptake.

I find it’s the opposite. My corals take up the nutrients and the algae gets what’s leftover, if any.

I ran extremely low nutrients for a long time, and when I would bottom out it is the turf algae in the scrubber that suffers. The corals get what they want, and then there isn’t enough leftover for the macro, and the algae dies off.

 

[Reef Builders]

There is at least one new paper that concludes that algea based exudates are not the primary organic compounds causing coral disease in the DDAM model. Although this is extremely emerging research and is competing with the 50+ papers saying otherwise it may be that cheato etc simply don’t produce exudates that contribute to virulent expression in bacteria. I plan to do a larger write up again a DOC 2.0 so to speak breaking down the newer papers that have came out since my other article last July.

I also plan to conduct some multi-omics experiments in the coming months on the effect of carbon dosing, fuge, turf scrubber etc.

Eli just bought a qPCR and I am helping him formulate gene targets of interest. Oceamo just released the organo-MS. These tools combined with the existing metabarcoding that Eli offers will reveal many answers in due time.

 

[VintageReefer]

I would feel safe saying Ulva Intestinalis doesn’t produce anything negative as well

 

[IntrinsicReef]

I manage reef tanks with refugiums, without refugiums, some with algae turf scrubbers, some carbon dosed. They can all acheive very fast growth ( excessive really after the first year or two of filling in.) I have not seen any noticeable slowing of coral growth with a turf scrubber or refugium.

That said, I have seen corals generally look sickly when surrounded by hair algae. Or when algae dominants a display in general. Hearing the discussions on DOC released by algae, I am thinking that might explain this tight area of negative effect I've observed. Maybe they are subject to concentrated amounts when surrounded by algae, but the DOC is removed by sponges and activated carbon etc in the water column? Not sure.

 

[Randy Holmes-Farley Verified Community Expert]

I was referring to CAC being a preferable method compared to GAC to export DOC due to pore size. CAC tends to have larger pores than GAC which allows

A) better adsorption of larger organic compounds

B) has less surface polarity so lower chance of ion attraction

C) it’s also designed for catalytic degradation so it can chemically break down DOC


In my mind it’s about macroporous vs mesoporous absorption at least based on the waste water papers I’ve read. Thus I would assume that CAC would have less of an impact on traces and more of an impact on DOC compared to GAC.

I was merely pointing out what I consider to be an incorrect statement in the video. It may be that CAC and GAC have different relative metal binding in a reef tank, but if true, it would not be because of pore size, IMO.

It would be nice to see real data from a reef tank on any GAC and its effect on trace elements. I’ve seen the Oceamo data, but that’s not reef tank water where many trace elements are bound to organics. Thus, GAC binding those organics will necessarily bind the attached trace elements.

 

[Randy Holmes-Farley Verified Community Expert]

if high DOC is bad, why does fauna marin sell carbon to dose? or some people dose vinegar. is carbon in a system good or bad? its kind of confusing to me.

The problem is lumping all organics into a single bucket. They include molecules with vastly different properties.