Does carbon dosing promote bad bacteria and can uv help the spread of rtn/stn?

[theoregonian]

I don't know if corals can get bacterial infections but here's a question. If you carbon dose could this promote unwanted,unknown bacteria that could cause rtn/stn to spread through a closed loop system? If you put a frag in the tank that has unknown bacterial infection wouldn't feeding the bacteria cause proliferation? Would a uv sterilizer help to keep a bad bacteria from overwhelming a closed system? I've heard of rtn/stn and was curious if in some cases it could be caused from unknown diseases and if uv would/could help to keep it from overwhelming the water column causing the healthiest corals immunities to weaken?

[ca1ore]

There is certainly some prevailing wisdom that STN may be bacterial in origin, though it does not appear (to me, at least) that RTN is. However, as somebody who runs UV continuously, I do not find it to make any difference to the spread of STN.

[CuzzA]

Necrosis is the result of a bacterial infection. However, corals are only effected if weakened. For example, a large swing in alk, sg, or temp. So while carbon dosing may feed this bad bacteria it likely won't directly result in necrosis. Weakening or injuring a coral may allow the necrosis to set in, whether carbon dosing increases the chances I don't know. From the studies I've read, in the wild the bacteria is not present on healthy corals, but instead resides on macro algae. But with our closed systems and macro algae refugiums a length of pipe away and the higher risk of swings I would have to assume that's why we experience a lot of necrosis in our tanks compared to natural reefs. I believe a UV sterilizer would be beneficial to keep this free floating bacteria under control. Especially if you could sterilize water transferring from a refugium to the main system.

[Sk8r]

My lps really expand out after a vinegar dose and one 3 head branching hammer frag has put on 3 or so new buds from the stony base since I started dosing, (it had been lazing along with 2 that weren't growing much) so something seems to their liking. I'm in a growth phase in this tank, meaning I started with small frags, including some distressed ones, and am trying to get them up to size. For what it's worth. It does seem to energize the lps. Could the sps, using more sunlight, need lower dosage?

[dkeller_nc]

An awful lot of use carbon dosing on tanks with all sorts of coral inhabitants (SPS, LPS, mixed, etc...) without ill effect, so it would seem that encouraging bacterial growth in general doesn't cause problems in and of itself.

Having said that, overdoing carbon dosing to the point where bacteria clouds the tank water and drastically reduces the tank's dissolved oxygen concentration has been reported to cause serious issues, including complete tank crashes.

Under such circumstances, UV might actually make things worse by killing large amounts of bacteria, which will liberate large amounts of cell contents into the tank water. A better plan for recovery of an extreme carbon over-dosing event, IMO, would be several large (>50%) water changes, and active removal of the suspended bacteria by mechanical filtration, such as with a diatom filter like the Vortex D-1.

[CuzzA]

I've dosed both vodka and vinegar and have noted some observation.

Vodka seemed harsh on the corals. In particular chalices and favias did not fair well and began to recede. The receding ceased upon haulting the vodka dose so from that I conclude, in my system anyway, that vodka had a negative effect. Nothing else seemed terribly effected although polyp extension also appeared to be less prevalent.

Vinegar on the other hand has been positive for all corals except ricordias. Polyp extension is terrible and in fact the first coral in my tank was a Yuma that had been doing fantastic since March of 2014 and has now since detached itself. This could be a direct result of the vinegar or just the fact that the nutrients in the tank are too low. Otherwise, everything else looks amazing. I've noted increased color and polyp extension. In particular my fleshy LPS (lobo, torch, frogspawn). Also, one coral that really stands out is my Sympodium colony, as it went from a royal blue to a vibrant tealish blue/green. SPS at this point are unchanged, but I suspect they will take a little longer than everything else in the tank because they are drama queens.

I have also noticed slightly more algae in the system, but I'm still dialing in my maintenance dose and I stopped GFO. I may put the GFO back online but at a small amount and reduced flow. Keeping tangs and feeding nori everyday, I suspect once nitrates are undetectable I'll still have slightly elevated PO4.

These are my observation anyway and it's still a work in progress only to do it all over again when the 300 arrives in a couple weeks.

[Sk8r]

I had trouble using GFO and vinegar. GFO stopped tumbling. Don't know whether this was bacterial or not: haven't yet had time to open the cylinder and check.

[CuzzA]

I suspect I would have the same problem as reactors tend to be a perfect breeding ground for bacteria. My carbon reactor grows 3 inch long strands of bacteria funk.

[droog]

Either promote the bacteria or sterilise them them. Trying to do both doesn't make much sense.

You could run UV at the onset of symptoms, but the bacteria from the dosing will die off if you stop dosing / do a quick PWC.

-droog

[Big E]

Originally Posted by Sk8r

I had trouble using GFO and vinegar. GFO stopped tumbling. Don't know whether this was bacterial or not: haven't yet had time to open the cylinder and check.

This is because the bacteria will grow inside the reactor clogging it up. If your going to run GFO, only use if for a week or two to knock down high levels than take it off line.

GFO also is going to steal PO4 from the bacteria........so it's going to make carbon dosing less efficient.

[Big E]

Originally Posted by droog

Either promote the bacteria or sterilise them them. Trying to do both doesn't make much sense.

You could run UV at the onset of symptoms, but the bacteria from the dosing will die off if you stop dosing / do a quick PWC.

-droog

UV doesn't kill bacteria........it sterilizes them so they can't reproduce. It's not going to have much of a negative effect, just like it doesn't have an effect on the nitrogen cycle. Most of the PO4/NO3 eating bacteria collects and thrives where it will be able to catch nutrients..........for example in/on live rock, filter socks, reactors, ect.

The skimmer is what actually removes or exports the bacteria out of the system and the need to continue to carbon dose to keep the population thriving.

There is some anecdotal evidence that UV promotes better skimming so it could actually help in boosting the % of bacteria that the skimmer removes.

[KAMIKAZE0214]

Originally Posted by Big E

UV doesn't kill bacteria........it sterilizes them so they can't reproduce. It's not going to have much of a negative effect, just like it doesn't have an effect on the nitrogen cycle. Most of the PO4/NO3 eating bacteria collects and thrives where it will be able to catch nutrients..........for example in/on live rock, filter socks, reactors, ect.

The skimmer is what actually removes or exports the bacteria out of the system and the need to continue to carbon dose to keep the population thriving.

There is some anecdotal evidence that UV promotes better skimming so it could actually help in boosting the % of bacteria that the skimmer removes.

Pretty sure you are confused. UV light damages bacteria and through that damage, kills them. You may have the idea of UV "sterilizing air" (by killing bacteria). UV kills bacteria which can then be skimmed out easier.

[Big E]

No I have the facts correct---

"2.3 Microbial Response to UV Light
The mechanism of disinfection by UV light differs considerably from the mechanisms of
chemical disinfectants such as chlorine and ozone. Chemical disinfectants inactivate
microorganisms by destroying or damaging cellular structures, interfering with metabolism, and
hindering biosynthesis and growth (Snowball and Hornsey 1988). UV light inactivates
microorganisms by damaging their nucleic acid, thereby preventing them from replicating. A
microorganism that cannot replicate cannot infect a host.
It is important that the assays used to quantify microorganism inactivation measure the
ability of the microorganism to reproduce (Jagger 1967). For bacteria, assays measure the ability
of the microorganism to divide and form colonies. For viruses, assays measure the ability of the
microorganism to form plaques in host cells. For protozoan cysts, the assays measure the ability
of the microorganism to infect a host or tissue culture. Assays that do not measure a response to
reproduction may result in misleading information on the inactivation of microorganisms using
UV light."

http://www.epa.gov/ogwdw/disinfectio...uvguidance.pdf

As far as the skimming goes..........it can export bacteria whether it's dead or alive. The part about the UV making skimming more effective has to do with the UV light breaking down organics and making them more available to skim. As I mentioned this is anecdotal.....I have never seen any UV manufacturer claim these as advantages of UV or read of any factual info concerning this.

[GPCRalph]

That's interesting. At first I was confused because I am aware of the use of UV light for the disinfection of surfaces but after thinking more about it, it makes sense considering the reduced exposure time in the water and to a certain extent the reduced penetration of the light would be enough to disrupt cell viability but cell death would be less likely. Even on surfaces we usually followed up with a germicidal wipe. Cool. I hadn't really thought about the way UV would actually affect the water. Thanks for the post.

Droog - I agree with you. I am getting back into the hobby. And I have been conflicted about why dose to increase bacteria while we use so many methods to reduce bacteria so have been curiously reading about people's experiences.

As an aside, UV sterilizers do presumably affect bacterial levels but I have been concerned that they would also knock out some of the good things in the water like pods and algae etc that corals, fish or inhabitants feed on. Anyone have any input about noticing any changes? That being said, I have seen some amazing full blown reef tanks growing just about everything from difficult sps to lps etc running UV sterilizers. Just to add more confusion to our anecdotal search of what works best.

[ArmyGreens]

"...reef environments choose a UV that matches your flow rate per hour in the 30,000 or 45,000 columns of our chart. Flow rates in the 75,000 and 90,000 columns will destroy the planktonic food supply ..." take from Aqua UVs descriptio. That is meaning 30k - 45k µw/cm2 is relatively safe. How those numbers are found for other sterilizers is beyond me, guessing it would something close to; FlowRate(wattage/volume)=µw/cm2

sterilization is not just for bacteria but things like free floating algae, pathogens and ionization effects.

[pledosophy]

I have never seen any evidence that carbon dosing promotes the growth of bacteria that cause illness in fish, or corals.

Just because it promotes the growth of certain bacteria, does not mean it promotes the growth of all bacteria.

[sonnus]

Mis posted......