Gouramis dead, worried about the rest

[Aindrea]

I had a giant danio, two gold gouramis, two blue gouramis, an white gourami, two flame dwarf gouramis, two blue dwarf gouramis, and a dwarf pleco in a 45 gallon tank. One of the blue gouramis died and I didn't know it until the giant danio died. I did a water (about 10% RO water plus Start Right, I was having issues with my tap water before and I thought this would be better) and filter change and found the blue under the plastic castle. I took the toys out of the tank because it made me nervous that I couldn't see when something was going on with the fish, or when they died.
Last night, I found the other blue gourami dead, and this morning, I found the white gourami dead. I decided to remove the fish from the tank before the rest of them died and I put them into another tank (fish in this tank are all doing fine, eating well). While in transit, the last gold gourami died.
All I have to test water parameters with are the dip sticks right now. I've never had problems with fish dying for no reason. Anyway, the dip sticks all show within "Ideal" or "safe" ranges, which probably means nothing.
nitrate - 40
nitrite - 0
hardness - 300 (always had hard water, another reason I wanted to use RO for some water changes)
Alkalinity - 120
pH - 7.2
This is a 45 gallon tank, and it has been set up for over two years, the only fish that has survived the entire two years was the white gourami, until today. I have a Marineland Penguin 200 (200 GPH, up to 50 gal), which is brand new as of about a month ago.
Currently, there are no fish in the tank. I put them in the other tank and I'm not sure what was wrong, so I'm not sure if that was a good idea. I thought if there was something wrong with the water, that it might be best. We will see. We normally feed the fish tropical flakes, occasionally the frozen brine shrimp. I thought maybe I was feeding too much and dropped the amount by about half for the last several days.

I am totally devastated. I am not handling this very well, as we have had issues with water changes in the past. I assumed that the water still had chlorine in it at that time and that was what killed the other fish. I'm just not sure what could be causing this. I have noticed that the fish that died looked fat, like they were eating too much or something and I was reading some stuff about constipation. Could this be it? The dwarfs I moved look okay so far, though one of them is breathing kind of fast.
I suppose it is silly to ask for advice for a tank with no fish in it, but I am worried about the fish that I moved. I just want to know what to look for and to treat them if I can in case whatever killed the others might take them as well.

Thanks in advance for any comments or advice. I tried to cover all the "before you post about sick fish" thread points.

 

[James_in_MN]

1) Test strips are notoriously inaccurate. You need to get a liquid test kit ASAP and retest your water. The most recommended on these boards is the API Freshwater Master Test Kit.

2) You have way too many gouramis in that tank. Male gouramis are territorial and will fight each other unless they're given enough cover to hide behind.

3) The fact that one of your gouramis is breathing too fast may be a sign of ammonia in the tank. You'll have to check that once you get a new liquid test kit. If you used tap water with no dechlorinator, you killed all of your beneficial bacteria, which will cause you to restart your nitrogen cycle.

 

[Aindrea]

1) Test strips are notoriously inaccurate. You need to get a liquid test kit ASAP and retest your water. The most recommended on these boards is the API Freshwater Master Test Kit.

2) You have way too many gouramis in that tank. Male gouramis are territorial and will fight each other unless they're given enough cover to hide behind.

3) The fact that one of your gouramis is breathing too fast may be a sign of ammonia in the tank. You'll have to check that once you get a new liquid test kit. If you used tap water with no dechlorinator, you killed all of your beneficial bacteria, which will cause you to restart your nitrogen cycle.

1) I will be getting a proper testing kit as soon as I can, but I don't feel it is an emergency as there are no fish in that tank anymore; I thought I made that clear.

2) Everyone was getting along fine until this week. We never had issues with any of the gouramis picking on each other. However, I was thinking that taking the decorations out of the tank may have been a mistake. I will be looking for some acceptable tank decorations.

3) The gourami that was breathing fast passed away tonight. As I mentioned earlier, I took them all out and put them into another tank. I think that he was stressed and if the water was poor in the other tank, he didn't handle a healthy tank very well.

The time that I used tap water, I did not de-chlorinate the water before hand. But that was a few months ago, so I don't think that it contributed to this problem. I haven't done that since.

I appreciate the feed back and I will be testing the tank more frequently. I would, however, also like some advice on how to get the now empty (no fish empty, not no water empty) tank re-set up. I am almost tempted to dump all the water, clean the gravel in the bottom, change filters, etc. to just start over. Would that be a good idea? I would lose all the beneficial bacteria...

 

[siva]

Gourami's, much like their cousin the betta, will often live together seemingly peacefully for some time before the problems start up. Keeping a large group of gouramis can work long term, in a heavily planted tank with a 2:1 ratio of females to males. Otherwise, it isn't advisable.

Don't throw everything out..it really might not be necesary. Did you add any fish in the week prior to this starting?

Gouramis, atleast the dwarf gouramis, do not do well with high nitrates. I doubt this is the cause of death, especially since you lost the danio as well, but 40 is high, especially on a test strip since it's likely actually 60. I always keep nitrates from exceeding 20. Ammonia poisoning could be the cause, were you able to test for ammo? Did any of the gouramis start to show darkening patches before dying..especially around the head area? Any other strange behavoir..sitting at the bottom alot, clamped fins, etc? Any white spots on anyone?

Bloating can be caused my swim bladder which gouramis are prone to but it seems unlikely they would all have it at the same time. What are you feeding them?

 

[Aindrea]

Gourami's, much like their cousin the betta, will often live together seemingly peacefully for some time before the problems start up. Keeping a large group of gouramis can work long term, in a heavily planted tank with a 2:1 ratio of females to males. Otherwise, it isn't advisable.

Don't throw everything out..it really might not be necesary. Did you add any fish in the week prior to this starting?

Gouramis, atleast the dwarf gouramis, do not do well with high nitrates. I doubt this is the cause of death, especially since you lost the danio as well, but 40 is high, especially on a test strip since it's likely actually 60. I always keep nitrates from exceeding 20. Ammonia poisoning could be the cause, were you able to test for ammo? Did any of the gouramis start to show darkening patches before dying..especially around the head area? Any other strange behavoir..sitting at the bottom alot, clamped fins, etc? Any white spots on anyone?

Bloating can be caused my swim bladder which gouramis are prone to but it seems unlikely they would all have it at the same time. What are you feeding them?

I hadn't added any fish for almost a month. And I know how inaccurate the test strips are, hence why I don't trust them. But they do give an idea of what is going on and I regrettably was not testing very often. All of the fish that died, except for the danio were darker, their markings were almost black when they passed away. They did sit idly about in the tank, sometimes at the top and other times at the bottom. I noticed that, but I guess I forgot to mention it. No clamped fins or spots though.

I was feeding them tropical flakes and since there was a pleco in the tank as well, I would put a piece of an algae wafer in there also. Occasionally, we would feed them mysis shrimp or brine shrimp, but that was rare as I usually forget we have them. Would the gouramis eat the algae wafer at all? Could that hurt them? I never noticed whether they tried to eat it or not.

 

[siva]

I hadn't added any fish for almost a month. And I know how inaccurate the test strips are, hence why I don't trust them. But they do give an idea of what is going on and I regrettably was not testing very often. All of the fish that died, except for the danio were darker, their markings were almost black when they passed away. They did sit idly about in the tank, sometimes at the top and other times at the bottom. I noticed that, but I guess I forgot to mention it. No clamped fins or spots though.

I was feeding them tropical flakes and since there was a pleco in the tank as well, I would put a piece of an algae wafer in there also. Occasionally, we would feed them mysis shrimp or brine shrimp, but that was rare as I usually forget we have them. Would the gouramis eat the algae wafer at all? Could that hurt them? I never noticed whether they tried to eat it or not.

Ok that's great, that highly lowers the chances that someone brought something in. I have seen gouramis with ammonia poisoning that got darker and acted strange then passed away. You said the filter you just got about a month ago..unless you used cycled filter media in that new filter, your tank might not even be finished cycling. If those fish have been in there the entire time, they've been exposed to highly toxic levels of ammonia and nitrite. Gouramis are paticularly sensitive to this..they do best in prestine water. Cycling with fish can require more than daily water changes to keep the fish alive. Are you familiar with the nitrogen cycle and the term cycling? Here are some helpful links:
The Aquarium Nitrogen Cycle
The (almost) Complete Guide and FAQ to Fishless Cycling
I just learned about cycling but I already have fish. What now?!
If your tank was not cycled before adding fish, I'm fairly certain that is what is killing off your stock. This is often referred to by folks not familiar with cycling as "new tank syndrome".

Assuming the shrimp were frozen and not freeze dried, that is a fine diet, including nibbling on algae wafers. Those foods should not cause probs with gouramis.

If the fish are in another tank where they seem stable for the moment, let them be for a while. Once you get yourself the master test kit, we'll be able to figure out exactly where you are in your cycle and take it from there, adding fish back in once it's safe.

 

[Aindrea]

Ok that's great, that highly lowers the chances that someone brought something in. I have seen gouramis with ammonia poisoning that got darker and acted strange then passed away. You said the filter you just got about a month ago..unless you used cycled filter media in that new filter, your tank might not even be finished cycling. If those fish have been in there the entire time, they've been exposed to highly toxic levels of ammonia and nitrite. Gouramis are paticularly sensitive to this..they do best in prestine water. Cycling with fish can require more than daily water changes to keep the fish alive. Are you familiar with the nitrogen cycle and the term cycling? Here are some helpful links:
The Aquarium Nitrogen Cycle
The (almost) Complete Guide and FAQ to Fishless Cycling
I just learned about cycling but I already have fish. What now?!
If your tank was not cycled before adding fish, I'm fairly certain that is what is killing off your stock. This is often referred to by folks not familiar with cycling as "new tank syndrome".

Assuming the shrimp were frozen and not freeze dried, that is a fine diet, including nibbling on algae wafers. Those foods should not cause probs with gouramis.

If the fish are in another tank where they seem stable for the moment, let them be for a while. Once you get yourself the master test kit, we'll be able to figure out exactly where you are in your cycle and take it from there, adding fish back in once it's safe.

This tank has been established for over 2 years, so I'm pretty sure it is well cycled. When I said I replaced the filter system, I meant just that. I didn't change anything else in the tank at that time. I figured that would be no different than changing a filter cartridge.