Fish Dying for no reason. Please help!

[csr1978]

Fish dying. Please help.


I am having an ongoing issue where another fish dies about every 4 days. I cannot figure it out. If anyone can shed some light, that would be great! Here are the particulars:


This is a 3.5 month old, freshwater, slightly planted tank. It was started on Jan 30, 2017. It is a 120 gallon aqueon 6’ long tank. There is an aquatop CF500UV filter running along with some LED strip lights. There is one wave maker at 1000 gal/hr running 24/7 for water surface agitation. I am using one 100w Eheim Jager Aquarium thermostat and one 200 watt thermostat. I also monitor the temp with two always on, displaying digital thermostats, the Seneye and a manual digital probe.


Inside the filter is the media it comes with, but I have added a bag of purigen and Seachem Matrix Bio Media (1 Liter). I have also changed the filter pads and cleaned the filter twice, and changed the carbon and purigen once.


I have one piece of driftwood (that I soaked for a few weeks) that has been “decorated” with live java moss attached to foam (I followed these instructions here:

). The substrate is the CaribSea Eco-Complete. There is about 2 inches of that on the bottom. There is also some plastic drainage cell sheets (Seen here:

) used underneath some “dragon” stone rocks (to protect the glass bottom). There is also some large 3” PVC sections hidden under the rock to create “caves” for the fish to hide. The Java moss is thriving.


I feed the fish with Omega One Fish flakes (https://www.amazon.com/gp/product/B0045K93JU/?tag=ff0d01-20). Occasionally some frozen blood worms in a hang on defroster cup. I really want to say that I do not over feed. I would say I put in a tiny pinch-worth each morning. Its regulated by an automatic feeder. The guidance on feeding is very vague.


I use a small amount of aquarium salt in the tank. About 30% of what the directions call for.


I do weekly water changes. They have varied over the months. I used to do larger water changes 25%-50%. However, lately I am doing smaller 5-15% changes. Originally, I was using tap water with Aqueon water conditioner, now I use Seachem Prime. I have since switched to RO/DI water in attempt to lower pH. Using RO/DI water has not affected pH at all, but has lowered my kH & GH.


Regarding pH, I originally only used the API liquid to test. Which is worthless if your number is in the 7.0-8.0 range as the tests for both pH and High Range pH are very generalized. What I do know is that my pH fluctuates from 7.5 during the day to 7.4 during the night (I think it’s the lighting, photosynthesis, CO2 and oxygen changes). The Seneye tracks this best.


Here are the chemical parameters. I am testing three ways: API liquid, paper strips and a Seneye monitor. I also use a calibrated digital probe for pH.


Temp: 77
Ammonia: 0
Nitrite: 0
Nitrate: 5-25
Copper: 0
kH: 2 (Was 6 with tap water)
GH: 5 (Was 8 with tap water)
pH: 7.4/7.5
Chlorine/Chloramine: 0


Here are the fish in the tank:
Marble Molly
Dalmatian Molly
Pearl Leeri Gourami
Rainbow Shark
Electric Blue Acara
Redstriped eartheater
GloFish Tetra Starfire Red x2
Angel Fish Blue Phantom Cross
Redheaded Severum (baby)
Goyder Rainbow
Praecox Rainbow
Redline torpedo Barb x2
Rainbow Shark


There have been in the past (RIP):
Honey Gourami
German Blue Ram x2
24k Molly x2
Pearl Leeri Gourami
Electric Blue Acara
GloFish Tetra Starfire Red
Cockatoo Dwarf Cichlid Apisto x2
Redline torpedo Barb
Swordtail platy



Here is some more history of the tank:

I bought my “tester” fish and everything was going great. No deaths. Tank cycled properly. Then, there was a bout if ich about three months ago. I got some Seachem Cupramine from the LFS. I followed the instructions on the bottle (don’t ever follow the instructions on the bottle as they are wrong! If you call Seachem they will tell you a bunch of important information that they were too lazy or cheap to print on the bottle). 11 fish died overnight. Apparently when the say don’t use with water conditioners, they mean wait at least 48 hours. I waited 6 hours. Chemical reaction killed fish. Ich remained. I used an herbal Ich med (KORDON 100% Natural and Herbal Formula Ich Attack-Ich Treatment) and 4 weeks later it was cured. Only 1 or 2 more fish died. The list of fish above does not include any fish that dies from ich. That’s a separate list and not my concern. The dead fish listed above have died systematically for no discernable reason.


I also used for a short time Seachem Flourish and Flourish Excel for the java moss, but it was unnecessary as the java moss grows great without it and I was experiencing a lot of brown diatom growth on the tank while using the treatments.


In the last 3 months, there have been no signs of illness. There have been no new fish. However, I lose about 1 fish every 4 days. They all die the same way. I find them acting differently (as in not how that fish normally acts), followed by struggling to swim or floating around too weak to swim. Finally, dead, stuck to the filter. It is sickening. Any info to help me would be greatly appreciated. Thanks for reading this LONG post.

 

[DutchMuch]

I use a small amount of aquarium

Everyone will kill me and rant on me as always for this; but in my eyes aquarium salt is useless, it only diluted the water IMO. Some say it can cure illnesses, then I say if you did regular good fifty percent WC's a week then you wouldn't have the illnesses... I do some personal methods of tank maintenance but its pretty much the casual barrreport usual. fifty percent WC weekly on sunday, EI dosing.... Double filtration, dutch aquascaped... not much to it, but if done right then nothing will go wrong fish wise unless someone or something adds something or removes something from the tank.
You say your fish are struggling to swim, then kind of just slowly die off. Any other physically visible symptoms? to me your params as for the quality of the water, filtration, and such seem A plus! I would kick up those WC's though back on track to 25 (big tank ik) to fifty percent a week, in between there maybe shoot for thirty or fourty, but if possible fifty. I want to say so badly its something in the water, anything near the tank you think could have got in? It sounds like SBD (swim bladder disease) which is caused by bad water quality, specifically ammonia. Could also very well be NTD that started a string or strain of bacterial or parasitic infections...?

 

[SFFishSticks]

Trying to alter your local Ph isn't usually worthwhile and can lead to crashes.

What are you adding to your RO water? RO or Distilled water by itself can kill fish as it will suck the nutrients out of them to equalize with the water.

I'd ditch the salt, skip the RO water, ditch any plant supplements for now, and up the water changes back to 30-50% until things stabilize.

 

[Sherlock]

Do you buy your RO/DI water or do it yourself? I've heard horror stories about what stores do to their RO water.

 

[eaglesaquarium]

I see 3 elements of major trouble in what is going on.

1- aquarium salt, even in a low dose as you mention is not a long term solution, freshwater fish are freshwater fish and shouldn't have salt added. Salt has its purposes, but long term use it not recommended.

2- a lot of your fish are being kept in water that is completely unsuitable to their needs. Hard water fish struggling long term in water that is too soft, adding the RO water to lower your pH destroyed the kH and gH levels that was keeping things on the straight and narrow. The fishes' bodies are working constantly trying to compensate.

3- your stocking is all over the place. Fish that have different needs, different temperaments are all together.



Add all 3 of these together and you get what you are seeing. Your fish are constantly stressed. Fish dealing with stressors like this are much much more susceptible to disease and will die slowly over the course of their time in the tank. Unfortunately, you are going to have to make some tough choices about your long term plans for this tank.

And it all needs to start with what type of water you have in you tap. That sounds like:
pH 7.5 or so,
kH 5 degrees
gH 8 degrees

I'd suggest finding new homes for any of your fish that are not native to waters like that. And repopulate with fish that are naturally found in those types of waters, and have matching temperaments.