Martin

Thanks so much for the added information all. I've literally watched every video you guys posted and read everything nice and slow, so please know the significant time you guys took to help with the situation was very thoroughly digested and taken in. It is incredible the amount of questions you unfortunately don't know to ask until the situation has already become a problem. Though, fund of knowledge grows, and I appreciate you all for it.

One last question @BrettD: Uh... when is this? (Sorry.) Thanks so very much for the vast amount of lessons learned in this conversation everyone. Basically going to slow it down for the time being and work on getting the tank better settled then. It's okay, more attention for my plants then! The experience was very frustrating at the start because nothing was seemingly wrong, but it sounds like some issues can be insidious enough to go undetected by inexperienced eyes. You feel bad when a little life form dies, because, in the end, it is still life. I walk away a little relieved to have learned something from it. The worst is going though this and learning nothing.

@Beardedbillygoat1975, thanks very much for the information. I have learned a TON from this conversation alone. The breakdown was great for me. To address your questions/comments: My usual routine consists of changing out the cartridge monthly per the directions on the package. Apart from this, I do roughly 20% PWCs every two weeks along with surface gravel vacuuming. This is also where I will periodically drop down more root tabs, prune dead plant leaves, etc. I idea of ammonia spikes was also kind of strange to me, but again, a lot of folks have mentioned it. Much like regular water testing I noted above, I had kind of expected issues of ammonia to have "delcared" itself a bit via visible symptomatology among the animal life. Much like humans, I would have expected more lethargy and whatnot, but I never saw any change in behavior. Anywho, it sounds like general consensus is that filtration needs to be addressed better, so I will tackle that first and report back later on. Thank you to all!

@BrettD, thank you for your insight. So I guess this is where I might be missing something. I see multiple folks mentioning potential filtration issues, but isn't this what regular testing is supposed to help you pick up on? I'm not asking that from the position to challenge anyone has I know there must be truth if several of you guys are saying the same thing. I'm more asking as a genuine question from the position of a person who is still pretty rookie with about 2 years under his belt. I had made sure to do testing and PWC/maintenance on a regular basis and I had kind of thought that issues with filtration/ammonia/nitrites/nitrates would present themselves with regular testing. The water parameters have literally been the same since I finished cycling the tank before initial stocking, and (as far as I know) the pH has been unchanged from week to week, hence my confusion. Am I looking at something wrong or looking at something too simply? @nabokovfan87, forgot to ask... I'm not sure I would move in this direction, but would running dual 10g HOBs be a valid consideration if i wanted to avoid the 20g HOBs? Just curious. Still going to look into modifying the filtration media like you said.

Sorry for the delay all... whirlwind few days. Happy belated Mother's Day to all you fantastic moms out there! @nabokovfan87, thanks again for your insight and taking the time to verbalize it all. To address your comments: I actually do have something like this already made. It is pretty moot at this point as I removed the floating plants from that tank. Also, I had shy'ed away from using it as I figured I was limiting the surface agitation of the water and possibly hindering oxygenation. I'm dumb in this area and don't really know how much agitation is needed for proper O2 diffusion so I tried to play it safe. Also, you are correct about the current HOB having a flow rate switch. It's not really an issue for this HOB since it is the 10g HOB. It was more a problem with the 20g ones as those seemed pretty high speed even at lowest setting. Now that I've removed the floating plants, I may need to just revisit popping in an appropriate filter. Thanks for the video, I'll make time to study up on it this week and see what sorts of tweaks I can make on it. Thanks for the suggestion. I think the most realistic thing I can do at this point is probably to move the heater to maybe the center of the tank and moving the small secondary pump to the back, thus circulating the warm water through to the HOB and hopefully get a better distribution of heat. As you have touched upon, I'm unfortunately limited by space due to the other hardware, chiefly the light. Hanging the HOB on the side wall isn't currently an option. I still have some small WonderShells I will probably put in the tank to help the GH. I had used them previously in my smaller 10g and they worked like a charm, but at the same time that was during my "chase the parameter" days and the fish seemed fine without them so I eased off. I'll try pop one in and get it up. @Torrey, thanks much for your insight! First and foremost, my original training was in emergency medicine so I completely understand your thought process! I spent 6 years in county ER here in Houston as an ER physician assistant. I approached this thing in the exact same way... "What is acute vs. chronic?", "What is the differential?" 😄To respond to your questions/comments: No worries, it is better not to assume. I usually do testing on this tank every week. This is the big reason I got stumped with this thing since the parameters have been unchanged for so long. Regarding the your above question about the "GH of 8". It was actually the oxygenation level. The test (Salifer O2 test, link above in previous post) I used literally just said "8". There were no units of measure... just... 8. The instructions likewise just said that for freshwater tanks, 8 and above is best. The GH value was 30ppm. I had forgotten to mention, I use ACO EasyGreen for my fertilizer and I dose the tank about 3 times every two weeks. I put down ACO root tabs about once a month or so, maybe sooner if the plants show any signs of need. Thanks for the info. I'm going to keep this one in the back of my mind as it is pretty low on my differential at this point. The fish don't seem to be avoidant of the area and the mystery snails tend to hang out on the darn thing. Besides, any new equipment will quickly earn me "one of those looks" from my wife. 🙃 @Brandxn, nope! Nothing new in the food/chemicals area. Same stuff I've been using since I started the hobby about 2 years ago! THANK YOU again everyone. You guys are a HUGE asset to our community!

@nabokovfan87, thanks so much for taking the time to provide such a detailed response; I appreciate it greatly. To answer your questions: I'll have to check on these at it has been some time since I have checked my tap water. When I started my first tank, I obsessed with my parameters until I learned I should not be trying to chase numbers (at least not obsessively). From that point, I just started to work with what I have. I do have some leftover WonderShells if you think I should dump them in. I had originally purchased and tried multiple HOBs that were designed for 20G tanks, but the output seemed so fast that the surface of the water was like a wake after motorboat rolled through. I've been keeping fish for maybe 1.5 to 2 years now, so maybe it is just my own inexperience and that is supposed to be normal? I had downsized because, at that time, I had a LOT of red root floaters and wacky currents like that are bad for them. I had tried everything to try to slow down the output, such as placing two filter cartridges and decreasing the flow rate as low as possible. The brand of O2 test is a Salifert O2 test (https://www.amazon.com/Salifert-OXPT-Oxygen-Test-Kit/dp/B00NMI6BP0/ref=sr_1_2?keywords=salifert+o2&qid=1651969418&sr=8-2). The filter media is the run-of-the-mill filter cartridges that are made for that brand of filter (TopFin, https://www.amazon.com/Silenstream-Refill-Power-Filters-Supply/dp/B087V6XRPF/ref=sr_1_3?keywords=top+fin+10g+filter+cartridges&qid=1651969554&sprefix=topfin+10g+fi%2Caps%2C109&sr=8-3). It is setup the "normal" way? Sorry, not sure if there are other, more creative ways to put the cartridge in the HOB. 😄 Regarding the flow of the tank, thank you, that was all very helpful and things that I had neither considered nor knew that I needed to consider. I actually have a total of 4 of the pumps pictured there. Would placing a second pump directly beneath the HOB return to circulate water back to the left side of the tank be a good option? The guppies to tend to like to swim against the flow of the pump, though, from the their behavior, I think it is more just playfulness? They don't seem to have any aversion towards the other parts of the tank. I do have a glass canopy for the tank, but I stopped using it some while back. It was just for convenience as the light has a very low profile and I would have to move it to open the canopy to feed the fish. I'm open to trying another filter if need be, but at the same time, I'm trying to nail down what we think the chief issue is. The big question mark for me is just that the tank was good and fine for about 8 months with no new factors/changes just prior to crash. I would have thought issues with filtration and such would have shown signs during water testing and much sooner? I could also just be an idiot. 🤣 @Flumpweesel, thanks for the suggestion, the heater doesn't seem to be having any issues. @Mmiller2001, thanks to you as well, I'll have to look into those products as those are two SeaChem products I've never heard of. I do have some equilibrium on hand, but will hold off until I look into that other stuff first. I'll have to try and figure out a solution to the whole quarantine thing. Trying to find space for another tank is my chief issue.

Thanks for the assistance all. I've posted a photo at the bottom of the post. To answer your questions: Thanks for bringing this up, I had completely forgotten. No quarantine was done, not for lack of desire, more so due to lack of a QT tank/space. I had thought about this previously, but did not consider it heavily given the first wave of deaths had occurred 8 months in without any new livestock added. No medications at all. pH: 6.8 to 7.0 Nitrite/nitrate: 0/20ish Ammonia: 0.5 GH/KH: 30/80 Temp: 74 O2: "8" (The test doesn't specify a unit of measure, only that a freshwater tank should be kept at 8 or above.) I forgot to mention in my previous post, I use a HOB filter that is meant for a 10G tank. I used to have floating plants that could not stand the rather violent waves created by one designed for a 20G. When originally setting up the tank, I tested the water parameters religiously to make sure this was viable and figured the amount of live plants would balance out the filtration. I change the filter regularly and parameters have always remained unchanged since its initial setup, so I don't THNK that is the issue? Highly unlikely. I keep all of my aquarium supplies in the Sterilite containers seen below the tank, away from any possible contaminants. I do have 3 kids, but none of them are in the habit of messing with the tank. I had considered this originally too, but I didn't see any with the telltale "spot" that would suggest it. Can NTD develop in an established tank without being introduced from an outside source?

Hey gang, Hope all is well in each of your respective corners of the universe. About 3 months ago, I posted about sudden and (to this day) unexplained mass losses to my 20G long, heavily planted tank... roughly 20+ neon tetra and 6-10 amano shrimp. The tank had been established about 8 months without any issues and one day, everyone started going belly-up over a period of about 2 weeks. Every last water parameter was the same as usual (pH, nitrite/nitrate, GH/KH, temperature) with the regular PWCs. Some of you kind folks recommended checking ammonia, copper, and dissolved O2, which I also did. Ammonia was trace, there was no copper, and dissolved O2 was right at 8.0, which is what the package said to keep O2 levels at minimum. Given this, I tried to address the O2 just in case, even though none of my fish have ever shown any of the signs of low oxygenation, and installed small power heads to increase surface agitation. I left the tank alone with the 5 surviving tetra for a few months, hoping "time would heal all things". The surviving neons and 2x mystery snails went on with life without issue for about 2 months so, I decided it was time to move forward. This time, I decided to bring a few guppies into the mix since they tend to be a little hardier. I restocked the tank back up to 12 neon tetra (that's including the 5 survivors) and added a male and 3x female guppies. Since I brought them home about 2 weeks ago, everything was fine for about 1 week, then the tetra started dropping like flies. It started off as maybe 1 dead neon every morning, then a jaw-dropping 6 in one night.. I'm now down to 3 neons left. I noticed most of the time I found them, the bellies of the dead tetra appear eaten. I had not observed any aggressive behavior from the guppies, however I have noticed the neons stopped swimming carefree as they used to and were now hiding among the plants. I can't rule out foul play nor can I say that the dead weren't snacked on after they were already gone. Today, I watched another neon engage in "death float" in a struggle to swim straight and he did not appear harmed in any way. I lost the male guppy along the way as well. Note, during this time, one of the female guppies had fry about a week ago, which I have isolated, but still in the same tank, and they all appear healthy with no apparent deaths. I don't know if I need to be considering diseases, but I don't see anything to suggest any sort of disease. All the fish seem happy and lively, and dead the next morning. I also would have thought the fry would be affected quickly, but they are fine. I'm completely stumped and just don't understand. Any additional insight would be greatly appreciated. As usual, thanks so much in advance.

Oh man... As a fellow RCS lover, I'm sorry to hear it. What size tank and how many shrimp were in there? I started my RCS tank about 2 months ago and am always checking it for warning signs. My other tank has really been struggling lately with a LOT of unexplained deaths, which has made me more paranoid overall so I watch the RCS tank like a hawk. I hope it doesn't discourage you from re-establishing the colony, those little guys are so fun to watch when they are out and about.

Morning all, Was just doing a little plant pruning this morning and noticed one of my mystery snails alive, but floating. Has anyone seen this? I can only assume air somehow got trapped in the shell?

Oh man, congrats on that win! Me personally, I'd load that thing up with wood, wood, and more wood, then put plants all over that bad boy!

Thanks for the input everyone. I finished the boil yesterday and have had each of them sitting in separate buckets since then. So far, so good! Slight tannin coloring, but that's it. No sign of any cloudiness in any bucket. Hopefully it keeps up!

Wow! Thanks for the great information! Never knew plants could be "poached" in a sense. I'm waiting to see how the wood fares in their new bath. Fingers crossed!

I'm late to this convo, but the tank is GORGEOUS @laritheloud!! And that aponogeton in the back!! 😍

Good morning all, I purchased a few small pieces of cholla wood for my RCS tank, and I had (fortunately) read reviews of folks who had a few pieces that would putrify the water when they put it in their tank. I did my regular due diligence when buying new decorations: 1. I soaked all 5 pieces in a bucket of water and saw that a heavy and smelly biofilm developed. I dumped the water and refilled it. It happened again. 2. I cleaned each piece in-depth with a small bottle brush to the point that the hollow of each piece of wood was open and clear (i.e. I could see from one end to the other without any obstruction). After doing that the smell had improved but I could still appreciate a faint odor. Now I am boiling the wood and plan to place them in their own individual containers of water to see how each one fares. Do you guys have any experience or thoughts regarding cholla wood? Do I need to consider just throwing away any pieces if this step fails? Thanks guys!

I would zip tie all 4 corners of the wall. On the top two corners, hold it up via suction cups as mentioned above. On the bottom two zipties, I would wrap lead weights around them and bury them in the substrate. This would help to prevent any animal life burrowing behind the wall and either dying there or disturbing it. Not foolproof, but it would help. Good luck and send us pics!

I've created several Subwassertang vines for my various tanks. From my experience, a wall shouldn't be too hard. I imagine you would follow an approach similar to a java moss wall, only with a mesh with larger holes. Basically, two sheets of mesh with Subwassertang sandwiched in between. The great thing about this plant is it is practically unkillable. Apart from drying it out, it will continue to grow and propagate. Good luck!

Hey gang, I've had my first batch of baby RCS, however I'm pretty certain those came from females that arrived to me impregnated, so I technically have not had any successful breeding so far. I was reading up on Cory's RCS breeding tutorial and was going over the part about maintaining a variety of foods. Do you guys have any suggestions? I'm currently only using ACO fish/fry food and I really like it since the bits are so small, it blankets the tank in a snowglobe effect so I'm more confident that all the shrimp will find some. I've been looking into Repashy, but there's a billion varieties and the reviews are always spotty about what animal life likes what. I'ev also looked into Bacter AE, but then I saw their line of products like Shrimp Baby and Shrimp Fit. I'm a little overwhelmed. Alternatively, the shrimp seem happy and active, so perhaps "it ain't broke, so don't fix it"? Any advice or recommendations from you super-smart big brains? Thank you!

Thanks guys, Would you recommend I wait a bit for them to grow a bit before I try? They are less than a week old... wasn't sure if that kind of potential trauma would shock/kill them.

Good morning all! I started a red cherry shrimp tank to try my hand at breeding and one of them recently hatched eggs. I hadn't thought of it before this, but how do you guys do tank maintenance with the shrimplets? I'm afraid I'm going to accidentally suck one up or crush one. Should I just wait for a bit for them to grow a little? Thanks in advance!

Plecos are practically immortal. I prefer shrimp myself, but yeah... plecos are like Superman having drank from the Fountain of Youth with Jesus as his best friend. I had a pleco as a kid and everything in the tank died (give a 10 year old control of a 10-gallon, go figure), except for the pleco. It literally sat in that tank without water changes, by itself, and continued to grow. It came to a point where we had to give it away because I was scared of it. IT WAS ALWAYS WATCHING...

Like many others have said, this is it for me. I posted here about a month ago about sudden mass losses to my long-established and stable tank... fish and inverts, but EVERY. LAST. TEST. looked fine. To this day, my 20g long still only has 5x neon tetra in it for fear of killing more animal life. It is one thing to suffer a negative outcome due to a mistake that you can identify and learn from, but it feels like a absolute loss when you suffer a "defeat" and learn nothing from it. Lame. On a brighter note, my cherry shrimp tank had babies!

I'll be away about 5 days. I've got two tanks, the 10g with the cherry shrimp above and a 20g long that is currently only housing 2 mystery snails and 5 neon tetra (had a mysterious, mass die-off a month ago). The 20g is pretty well established in terms of plant life, the 10g is roughly 2 weeks old. Don't know that an auto-feeder is needed just yet, but I'll poke around for quality extended-release foods.

Hey guys, I have a planned vacation coming up in about a month and wanted to get ideas on what you guys do to feed the fish/inverts while you are gone. I've seen some tablet-like things in the local PetSmart, etc., but wasn't sure if that was the best way to go. What do you guys do? Also, while I'm on the subject of feeding, I recently started a (cherry) shrimp tank for the purposes of breeding, but I'm never really sure if I am feeding them enough or too much. It's always easier to tell with fish because you see them come and pick off the food, but the inverts always have to hunt it down after it hits the ground and I'm never really sure if they are getting the right amount. Any insight? As usual, thanks in advance to this fantastic community!

Monte carlo is the plant I want to love, but I don't. I find more often than not, it gets dislodged from where it is planted and ends up anchored to the substrate in one spot and the rest just kind of floating. I guess it all depends on the animal life you plan to keep, but my shrimp and snails uproot it easily. Very aggravating for my OCD lol.