Smrgle

@Whitecloud09 Ammonia is 0 according to the API master test kit. One dead guppy did have a long white streamer coming out of it's side. No other fish had "burst" although some had been partially eaten.

@ColuI did not check ammonia, but I have no reason to suspect there is any (well established tank, under gravel filter, no odd behavior in surviving fish). I did not quarantine. Fish kept color up until death, no water change recently, no chlorine in the tank. I don't add dechlorinator when doing water changes, and have not for the past 7 years. @Whitecloud09 I do have a liquid test kit, but this tank has been set up for over two years at this point, and is very well seasoned. I am happy to answer questions! I tend to leave out things I don't think are relevant, which is not great here

I have had a 40 gallon planted tank set up for over two years with angelfish, cardinal tetras, a few elderly guppies, and a pair of bushy nose plecos. Two weeks ago, I took a risk and added four angelfish to replace a few I had lost over the years. Yesterday, fish started dying. I have lost 1 pleco, 7 cardinal tetras, both guppies, and the only remaining original angelfish. 3/4 of the new angelfish are still alive. There are no signs of distress (clamped fins, wasting, flashing, refusing to eat, etc.), nor obvious disease. One cardinal tetra had an apparent skin lesion, but it survived through the night and into today, while four other fish died during that time. I started the first round of erythromycin and general cure last night. The 9 other tanks in my fish room are functioning normally. Attached are the water test and fish I have removed but not yet disposed of. Thank you in advance for any help or explanations you can provide.

I'm doing my undergrad majoring in marine biology. I'm still at the point where everything I learn about fascinates me. I currently want to study coral reef ecology, but the professor I am eyeing for graduate school studies the development of lateral lines in haplochromine cichlids. I also coach fencing part time at my local club, which funds my hobby very well.

My dad objected to an air pump set up in the basement below the master bedroom, so the first day I had it, I never told him about it. He didn't even know it was in the house until I showed it to him. For me, the only nose from the air pump is from the excess air vent. I have a gate valve for more specific control of how much air is released, and following that valve I have the pvc bend several times with elbows to break up the path of the sound. I also capped off the end of the pipe and drilled small holes (repurposed a water change intake) to muffle the noise even further. Even though the valve is built into my rack system, the sound of bubbles at the surface is still far louder than any sound the pump makes!

I have a 16 inch (estimated) clown knife. I got it at 4 inches and it grew about an inch a month for the first 10 months, and then two inches in the following year. He graduated from a 1.5 inch pvc y fitting to a 4 inch fitting. This is Jaws from last May,

I am unsure, all the fry seem to be at the same stage at this point, and I never found any dead ones at the bottom of the tank, so maybe? I really do just think she laid some eggs a few days after the initial ones, and when the initial group was ready to be moved around the tank, she picked up the ones that were still underdeveloped too. Either way I have at least 70 fry so I can't be sure if the dozen or so late starters made it.

If this overcomplicates things and leads to less understanding feel free to completely ignore it, but a parallel can be drawn with vinegar eel cultures. The bacteria feed on the sugars from the apple slices (in this case the apple was the primary producer) and the vinegar eels feed on the bacteria. Fish that eat bacteria tend to go after biofilm, not individual bacterium which are far too small. The ecosystem growing in the paramecium culture takes energy from the sun and repackages it several times until it is in the form of something palatable to the fry. As a side note the idea of algae being all classified together is a bit simplified. Bacteria were the first ones on the planet to photosynthesize and photosynthesis has only arisen in bacteria. The organelles that allow things we call algae to photosynthesize are actually reduced bacteria that lost their DNA to the nucleus of the host cell. This is called endosymbiosis.

Silver Tip tetras. I started to try to build up a school for my 120 last year, and lost 12 out of 15. Just bought 10 more a few days ago and already lost 2. Meanwhile the harlequin rasboras and monk tetras I got from the same store all made it through quarantine and the rasboras are pushing 1.5 years with 13/15 surviving.

I struggled with Val too. I had it for about a year and it carpeted about half of my 120 with nothing but inert gravel and liquid fertilizer, but it would only get about three inches tall. When I redid my tank I put a few root tabs in the gravel and also upped the light (two fluval 3.0 one maxes out at 50, the other at 75) and now it reaches the surface. I am not sure what change helped it, the light or the root tabs, but if height is the issue I would try to see if the light could be increased!

@JRaffyI have a couple of 75's set up with stingrays and I always seem to struggle to grow plants. For a brief time I had a fluval 3.0 on a 75 to grow wisteria, but the bright light seemed to be stressing the inhabitants out (sounds like this won't be a problem for your stocking). I would definitely go with the 3.0 if trying to grow plants too! I also remember being told that frogbit needed a ton of light, like insane amounts of light, but I was kind of listening into that conversation so maybe I misunderstood! Good luck and definitely post pictures!

My kribensis spawned last week, and aside from having them for less than two days before they laid eggs, I was also surprised to see the state of the fry when they first moved them. Most of the spawn was free of the yolk sac, but maybe two dozen of the fry still seemed to be in the "ball with a tail" stage. Is it possible that the female laid more eggs a few days after laying the first batch and these are just less developed? At this point that is the only hypothesis I can think of. I think her attempt to move them with the more developed fry is going to kill them, which is unfortunate but I don't think there is anything else to do about it. (Sorry if the photos appear upside down, I am not sure if that is just a preview thing)