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Cas8100
05/13/2018, 09:14 PM
Hey all,

I need some thoughts on my tank. I have an Innovative Marine Nuvo 40 that has been running for about 20 months. I have been running a Reef Octopus HOB 1000 skimmer, which is slightly oversized for the tank. Tank is well stocked (2 clowns, 4 chromis, bicolor blenny, cleaner wrasse, bengai cardinal, and cleaner shrimp). I dose 2-part daily to maintain alkalinity around 8.5. I had been doing daily 1/2 gallon water changes that maintained Nitrates between 10 and 20.

I recently turned one of the back chambers of the Nuvo into a refugium and discontinued the water changes. I have the refugium lit for 10 hours each night growing chaeto. My goal was to provide a better breeding ground for pods (would really like to support a mandarin) and also to be able to get away from doing so many water changes.

Within 2 weeks the chaeto had filled the chamber and my nitrates dropped to levels undetectable by my Red Sea test kit. My skimmer production has dropped to near nothing. My concern is that the nutrients are now too low.

I'd love to get rid of the skimmer as it's very loud. Does the skimmer anything for the tank other than nutrient export? ...And will the chaeto alone do the same job, providing that it can keep the nutrients low (enough). Any thoughts?

Or... does anyone have thoughts on keeping the skimmer and discontinuing regular water changes? I'd thought about dosing with something like Seachem's Reef Plus or Reef Trace to make up for the elements normally obtained from the water change.

Thanks for any input.

CS

zachfishman
05/13/2018, 09:36 PM
I like skimmers in part for helping with gas exchange. If you’re worried about low nutrient levels, you could feed more and/or decrease the photo period on your refugium.

Subsea
05/13/2018, 10:37 PM
For me, there are many negatives to using protein skimmers.

First, the nutrients taken out by skimmers and the nutrients sequestered by refugiums are totally different processes.

Skimmers skew free swimming bacteria populations and remove zooplankton, both of which are nutrient export. Macro algae refugiums sequester nutrients to be exported or recycled into feeding fish. Pod refugiums work well with macro refugiums as macro surfaces allow biofilms that feed zooplankton. Copepods recycle nutrients into live food. The adults feed fish and the larvae feed corals.

I have been skimmerless > 30 years and water change every six months.

ReefPharmer
05/14/2018, 03:48 AM
For me, there are many negatives to using protein skimmers.

First, the nutrients taken out by skimmers and the nutrients sequestered by refugiums are totally different processes.

Skimmers skew free swimming bacteria populations and remove zooplankton, both of which are nutrient export. Macro algae refugiums sequester nutrients to be exported or recycled into feeding fish. Pod refugiums work well with macro refugiums as macro surfaces allow biofilms that feed zooplankton. Copepods recycle nutrients into live food. The adults feed fish and the larvae feed corals.

I have been skimmerless > 30 years and water change every six months.



Can you please share a pic of your tank ? Thanks !

Subsea
05/14/2018, 05:38 AM
https://m.youtube.com/watch?v=FDt8QTAp0Cs

Video is 5 years old.

mcgyvr
05/14/2018, 05:41 AM
I'd love to get rid of the skimmer as it's very loud. Does the skimmer anything for the tank other than nutrient export? ...And will the chaeto alone do the same job, providing that it can keep the nutrients low (enough). Any thoughts?

Or... does anyone have thoughts on keeping the skimmer and discontinuing regular water changes? I'd thought about dosing with something like Seachem's Reef Plus or Reef Trace to make up for the elements normally obtained from the water change.

Thanks for any input.

CS

What type of corals do you have?
Have you noticed any negative reactions in them now that your nutrient levels are lower? (loss of color,etc...?)
What are your phosphate readings?

Cas8100
05/14/2018, 07:01 AM
What type of corals do you have?
Have you noticed any negative reactions in them now that your nutrient levels are lower? (loss of color,etc...?)
What are your phosphate readings?

Mcgyvr,

No loss of color, but it seems like growth has slowed down significantly. Thatís what got me looking at nutrients being too low. Maybe Iím creating problems where they donít exist.

As far as corals go, I have some montepora, lots of star polyps, Xenia, stunner chalice, zoas, clove, mushrooms, hammer coral, and birds nest. I donít have a phosphate test kit, but I assume the levels are at least balanced with nitrates because I donít have any algae or cyano issues.

Iíll try and post a photo in a bit. Have to figure out how to do it so that size requirements are met.

Cas8100
05/14/2018, 07:09 AM
Dropbox seems to be easiest for sharing photos.

https://www.dropbox.com/s/9ybxmflu24lxzqw/IMG-0007.JPG?dl=0

Cas8100
05/14/2018, 07:10 AM
I have been skimmerless > 30 years and water change every six months.

Subsea, do you run an airstone to help with gas exchange?

mcgyvr
05/14/2018, 07:20 AM
Mcgyvr,

No loss of color, but it seems like growth has slowed down significantly. Thatís what got me looking at nutrients being too low. Maybe Iím creating problems where they donít exist.

....

I donít have a phosphate test kit, but I assume the levels are at least balanced with nitrates because I donít have any algae or cyano issues.



Have you had to change your dosing schedule?
If not then it may be all in your head... If the consumption is still the same then I kind of doubt growth has been effected much if any..

and you know what they say about "assume" right? ;)

Cas8100
05/14/2018, 09:52 AM
I didnít think of changes to dosing as a measurement for growth rate. Good thought. I dropped my dosing by a very small amount a couple days ago, but Iíll keep track of that moving forward.

My ďAssumptionĒ is largely that my wife will get ****ed if I spend any more money on the tank right now, but a Hanna checker will hopefully be in my near term future. I never really worried about phosphate levels until now based on the fact that my AIO tank isnít really plumbed to easily add a GFO reactor. So I figured there wasnít much I was going to do about it anyway. Probably not the best mindset.

Subsea
05/14/2018, 10:34 AM
Subsea, do you run an airstone to help with gas exchange?

With gas exchange being critical in a reef tank, it is the only pro that I give protein skimmers.

When Reef tank flow dynamics are correct, gas exchange should never be a problem. For my tanks with sumps, surface skimmer overflow box removes crud and decreases surface tension to allow better gas exchange in display tank. As water leaves the display tank, it cascades over rock rubble in first chamber of 30G EcoSystem mud macro refugium. On tanks without sumps, I use agressive circulation to keep surface water agitated.

It should be noted, there is more gas exchange at the tank surface, then at the protein skimmer gas bubbles.

hkgar
05/14/2018, 02:17 PM
To me, skimmers do the function of the breaking waves coming to shore and they seem to be high in phosphorus.

Cas8100
05/14/2018, 09:31 PM
Thanks all. Iíll cruise the way it is for a while and watch for any degradation in the corals. Iíll post back here if I encounter anything worthy of discussion.

Thanks again.

Subsea
05/15/2018, 05:37 AM
https://www.advancedaquarist.com/2010/2/aafeature

Protein skimmer analysis of skimmate.


Other Feldman articles show effectiveness of protein skimmers on removing TOC (total organic carbon)

Protein skimmers at 29%
GAC at 70%
Biofilter > 50%

PS. Remember, organic carbon grows bacteria.