Maybe I have bacterial infection this time?

[beanbag]

Hello folks, 

Long time no post.  Anyway, my "usual" Taiwan Bee tank had been running more or less OK for a while now, minus the "short antenna disease" problem that afflicted some of the shrimp.  But those eventually died off and the rest thrived.  Then due to [reasons] I had to leave for 6 months and had somebody else come in every 1-2 weeks to take care of the tank.  The food was via autofeeder now and the tanks got water changes every 2 weeks with the same water I usually mix (RO + remineralizer).  Some time a few months in the HMF filter completely clogged - can't vacuum out, so we rigged up a bypass mesh filter.  Some time later a section of monte carlo overgrew and lifted up.  A whole bunch of moss and floaters also overgrew, generally blocking the water circulation.

By the time I got back the tank was in bad shape.  With a clogged filter there was a whole bunch of slimy brown crud growing behind it.  There were about the same amount of shrimp as before, which in a way is bad because there should have been more if things were going well.  Also while about half the shrimp were actively grazing around the other half were quietly standing around.  Then I noticed that there were a few shrimp dying per day, but usually they would quickly get eaten.  The almost-dead ones I was able to pluck out in time didn't have any obvious problems in appearance.   I did the following things, all separated by a few days, and it did not stop the loss of shrimps:

Half dose Erythromycin

Half dose Minocycline

removed a LOT of moss and floaters

Realized nitrates were very high (40+ ppm) and started doing 25-30% water change every day.  (usual level is less than 5ppm)

Removed the clogged HMF filter and replaced with a new thinner one.  vacuumed out a LOT of slimy brown sludge.  Yes this is a big change in bacteria content, but there was no way to salvage the old one.  Dosed some Seachem Stability and Prime.  I figure the rest of the tank still has enough surface area for nitrifying bacteria?

Somewhere along the way I dosed H2O2.

Half dose Praziquantl because I did notice some lethargic golden bee with the short antennae.

Add Indian almond leaf and some alder cones.  pH around 6.2 now, whereas before I left it was mid-upper 5's due to some peat pellets.

Currently I'm on day four of the "Flip Aquatics antibiotic treatment program".  See at the end of the post: 

The procedure is half dose antibiotic first day and 3rd day.  Why do I believe this?  The main reason is that he has done it multiple times and it worked.  Unlike some of these other common "cures" like "try adding botanicals, H202, feed certain foods", which maybe work and maybe don't.  And also, yes I know that this site's articles mention oxytetracycline, and I even got a bottle of it, but haven't tried it yet.

So anyway, it seems the loss rate has stopped or slowed for now, although about a quarter of the shrimp are still quietly standing around, and some have the short antennae.  I know from past experience that the antibiotics I tried won't cure them, so hopefully the prazi will (or maybe some other anti-larger-than-bacteria-med.)

 

 

With all that said, I have a bunch of questions, and I'll put them at the end here because the post is already too long:

Any suggestions for what else to do?

What could have caused the problem in the first place?  Poor water flow from clogged filter, high nitrates from either autofeeder overfeeding pollution?  (Why would there even be high nitrates if the plants are overgrown?)  Maybe the tannins from the botanicals ran out? 

When the monte carlo lifted up it exposed a lot of mulm.  Is it bad  for shrimp to get exposed to and eat that?

Should I try to get the pH back down into the 5's via peat?

Tempted to feed some "immunity boosting food" like Shrimp Fit, but that's a powder that will get all over the tank, so I'm worried it will create water pollution.

Maybe it's not a bacterial infection after all and they'd afflicted by something else?

What makes diagnosis really difficult is that it seems shrimps can get "hit" by something, then not get cured when that something is removed, and die a long while later anyway.

Edited July 27 by beanbag

[beanbag]

Update: I will start "operation lower pH via peat".  Even though this will add an additional variable on top of everything else, 

1. Lower pH is more anti-biotic and more protective against ammonia

2.  The pH before this whole incident was below 6, and it's 6.3 right now.  (The peat already in the tank before I left had run out in the meantime)

Edited July 28 by beanbag

[beanbag]

Much later update:

After only one addition of peat, the pH was in the upper 5's.  Without doing much else to the tank, there would just be cycles of good weeks and bad weeks.  Various meds I tried like Maracyn 1&2, prazi, and Metro did not solve the problem permanently.  Then I did another round of peat to drive the pH down to the low 5's plus started dosing Shrimp Fit.  Amazingly, one shrimp that had the short antenna disease got cured and grew it's antenna back.  This also caused the longest yet "good streak" of one month+ with very few deaths.  Plants started growing faster and more algae formed on the walls.

But alas, this good streak came to an end and the short antenna disease and random deaths came back.  The only difference I can think of now is that nitrates are higher, maybe 10+ ppm.  (Hard to tell on the API test kit)  Perhaps due to overfeeding (even though the shrimp finish the food in a few hours), or "old tank syndrome".  Like maybe too much poop in the substrate and so nitrates keep coming out and the plants somehow can't absorb it fast enough.  Or maybe water pollution, and nitrates are just an indicator. 

For now I change the water more frequently and starting using Seachem Purigen to help with the nitrate issue.  I've done gravel vac in the past, and assume that removing mulm removes a big source of nitrates. But then again, every time I do a gravel vac a few shrimp die over the next few days.  (probably kicked up bad stuff)  Maybe try dosing H2O2 regularly?

Well anyway, a very experienced shrimpkeeper told me that sometimes a particular tank can just kill off shrimp for no obvious reason, so may as well start another tank from scratch.

 

[sdlTBfanUK]

Sorry to hear you are still having this issue! You could try another aquarium but I would keep everything new and seperate so it will be a slow process. I would get new shrimps for it as well when it is ready!

My 'incident' with the heater caused the new trial to not work and I don't really know why to this day? I don't think there was anything wrong with the setup or tank, it worked before the incident well and I used all new stuff except the tank. It has put me off trying again so that tank is still empty and I keep looking at it thinking I should try again (then I think of what that involves), but after the last attempt failing for some unknown reason I can't get the incentive to try again as it is such a long, expensive, time consuming process which may just fail again! It is very frustrating, as you know, when you can't work out why it fails and everything seems 'ideal'. 

My betta is doing well and has some red cherry shrimps in with him and a friend gave me some small slightly blue snails and they are breeding wildly, so that tank is doing very well!

Good luck and hopefully you'll keep us informed/updated.