How to kill denitrifying bacteria

[gdemos]

I know there's no Biological forum but figured chemistry is close enough:

I've had some recent sludge build up issues with my BIOPELLET reactor and have belief that it is due to the 'additives/fillers' in the pellets I've been using. Logical conclusion given the pellet brand is really the only thing I've changed with respect to my three year run rate with my BIOPELLET reactor.

Two questions: any idea what additives may be with certain BIOPELLET brands and Amy idea technically what the sludge is? It bulbs up significantly to clog reactor plumbing.

Second: part of the sludge cleanup is taking down the reactor, cleaning all plumbing pumps etc AND rinsing media (pellets). So temp fluctuates, air exposure etc And if I were to rinse media with RO vs tank water...would this "kill he denitrifying bacteria"?

I will say that just four days following the reactor cleaning and media rinsing, I can see the sludge returning. I will be switching to a reportedly more pure BIOPELLET.

Thanks
Greg

 

[Zack33]

Is this sludge at all possibly build up of detritus (can be seen as many different forms)? Do you have filter socks/floss or anything before the reactor?

What brand of biopellet are you using/have you used in the past?

Finally, yes an RO rinse of the pellets can be enough to kill your beneficial bacteria, since bacteria are often "simple organisms" a change in salinity levels like this will cause cellular rupture as the osmotic pressures will change so dramatically, and therefore yes the bacteria will begin to die.

 

[gdemos]

Thanks for the reply. I was using NOPO pellets for over a year (reef dynamics brand) and currently running TLFISHES brand which I may correlate to the sludge. TLF brand running for 4 + months.

I am preparing to eliminate TLF Brand and switching to doctor tims based on recommendation.

This reactor is fed by manifold off my main return pump and effluent is plumbed to skimmer intake.

I really don't think it is detritus. It is nasty thick snot sludge.

 

[redfishbluefish]

It sounds like it's the bacteria that is not sufficiently getting sloughed off the pellet. What brand reactor are you running? And are the pellets tumbling?

 

[gdemos]

Reefdynamics 500
I know it sounds like a flow issue, but believe me
I've run it successfully for about three years and pretty sure this sludge has nothing to do with flow/recirc/tumble as is commonly associated with reactors. I have no reason to fault the reactor design and am fairly convinced it is the media

 

[Kungpaoshizi]

I had similar situations happen with ecobak v1 and v2 before I ditched the RD reactor and the pellets for nopox..

I'm a full believer now in that reactors like that, cannot keep up with exposure rates like the rock in the tank is exposed to, so it's a battle you can't really win. I finally got fed up with it and turned the reactor up over time, but it still resulted in an unstable situation that led to necrosis from the base upwards. Luckily I didn't lose anything, but it took months to recover..

 

[gdemos]

sorry to hear you struggled with the reactor. I read up as much as I could before getting on the biopellet reactor path; there was more anecdotal stories than steadfast how to info, but I did get a lot of help on my forum post:

http://www.reefcentral.com/forums/showthread.php?t=2457099

my reason for posting on the Chemistry tab was to try and find out if indeed it is the media "Fillers" that caused the sludge, if those "fillers" could be defined, and if there could be a determination for sure that the sludge was a direct result of the media as was suggested on my "Biopellet Reactor Tuning" quandary.

When running a Heavy Bioload/SPS Tank, biopellet seems to be an ideal nutrient export/carbon dosing application for the way I run things. I really didn't want to go to ATS, vinegar dosing...and I became pretty comfortable with biopellets through my trials. this is the first real problem I had outside of a brief stint with Cyanobacteria on the sandbed (which also happened only when I switched from NOPO to TLF brand pellets)

 

[Randy Holmes-Farley]

I cannot say that the fillers (if any) are the sludge in this case. It could be all sorts of things, including unusually high molecular weight polymers that are not as easily hydrolyzed.

I do know that some brands have fillers which would not dissolve, but I cannot disclose the filler or brand, and I do not know if the brand used here contains them.

So undissolvable fillers are possibility.

 

[gdemos]

i ended up dumping all my TLF pellets in exchange for Dr Tim's brand. the hope being that this brand change with 'no fillers' would solve my problem with sludge build up. well the sludge has returned. its different than the TLF stuff which really was like a polymer as RHF noted. the stuff now is a nasty slime/sludge that seems far more biological in nature. it clogged up the plumbing on the reactor, slowing the recirc. while i've always 'tumbled' well by what most would say is necessary to fluidize the pellets, if anything some would suggest my tumble is a bit aggressive, my only thought is to tumble more aggressively to shed more; or to make the reactor break down and clean out part of a monthly routine. NO3 and PO4 are testing okay [.02-.05 salifert; 0-.06 ULR]. Or, go back to the NOPO pellets that RD used to sell as a last ditch. some would suggest that 'overdosing carbon' would lead to this type of problem but i'm not sure of that given the parameters i'm testing at, sps look good.

perhaps it is the amino i'm adding (pohl's extra, A power, fuel -- i switch up brands with a 5 mL dose 5x weekly), heavy feeding and therefore 'extra effort' on part of the bacteria.

i'm not complaining about having to clean pumps and plumbing lines but this build up is excessive.