Losing fish daily - help please

[Raws69]

Request Help. Over the last few days lost a number of guppies and 1 gourami. Several or not looking good. Done an early water change to the normal schedule thinking this might help but no.

Tank size: 105 litres
pH: 8.2
ammonia: 0ppm
nitrite: not tested
nitrate: 40-80ppm really difficult to tell (api master kit)
kH: 15d
gH: 8d
tank temp: 24.8. 9 (did drop to 24 during water change 30lit)

Fish Symptoms (include full description including lesion, color, location, fish behavior): Gourami no loss of colour started swimming vertical And looked like just using tail, then sinks to bottom but when disturbed swims off. Guppies some disappeared overnight, 3 were swimming erratically then stopped, slight loss of colour. No lesions or white spots on scales on any of them.

Volume and Frequency of water changes: weekly 30l

Chemical Additives or Media in your tank: volcanic media, no chemicals other than water conditioner at water change

Tank inhabitants: Guppies 12 tetra 12 and gourami 3. None of the tetra are showing any signs of distress or behaving abnormal.

Recent additions to your tank (living or decoration): 4 female guppies and 2 female gourami.

Exposure to chemicals: None

 

[HoldenOn]

One problem right off the bat, guppies are hard water fish whereas tetra and gourami (especially) are soft water. I have little to no knowledge on disease so I will not comment. I would recommend testing your nitrites. 40 ppm for the nitrate is pretty high. You could probably benefit from some large water changes, but get a second opinion.

 

[FishGuest5123]

I agree that nitrates are too high. Someone with more experience with Gourami’s will be here. You need to know your nitrites too.

 

[Raws69]

But the tetra are fine. I have hard water but then why are the guppies suffering?

 

[Raws69]

Will test the nitrites shortly and post results

 

[AdoraBelle Dearheart]

How long has the tank been set up? How often do you clean your filter and do you use tank water or tap water to rinse the media?

When did you add the new fish to the tank?

 

[Raws69]

Tank has been up and running for about 8 / 9 weeks, filter is cleaned every 3 weeks. Media was rinsed in tap water as set up. The new gourami were added last wed, the 4 guppies last sat.

 

[AdoraBelle Dearheart]

I think you overstocked before it had really finished cycling or before your bacterial colony could handle it. It's possible you didn't see the ammonia spike, and that ammonia had been processed by the filter and/or any live plants before you took a water test, but your fish are still suffering the effects, especially since the nitrates are very high.

You haven't rinsed the filter media in tapwater since first setting up, have you? Have seen people do that before and crash their cycle, since the chlorine in the tapwater put in there to kill bacteria also kills the beneficial bacteria in the filter.

 

[AdoraBelle Dearheart]

I'm sorry, I forgot to say what you should do next.

Regardless of anything else, do an emergency 75% water change. Nitrates are too high, and clearly something is killing your fish, so first thing to do is a large water change. Make sure to temperature match the water you're refilling the tank with to the tank water temp, and use a water conditioner.

Save a little of the water you've removed so you can test it again.

 

[Essjay]

While you are doing the tests, test tap water for nitrate as well. The legal limit for nitrate is 50 ppm and some areas have almost that in their tap water. When tap nitrate is high it is not easy to get the tank nitrate level below that of the tap water.

 

[Guppy10]

How would you ever get nitrates below the level of tap water ? My tap water is about 20 and my tanks are the same and always are. Can you explain how you can ge lower nitrates in a tank ? Unless you use Ro water.

 

[Essjay]

You have to remove the nitrate before it goes in the tank. Some people use a Pozzani nitrate filter; others have had success by leaving the water to stand in a tub full of plants. Or mix with RO water, but that will also change the hardness.

 

[Raws69]

Tank nitrite is zero. Tap water nitrate is around 20/25 ppm.

 

[Essjay]

Your tank nitrate is quite a bit higher than your tap nitrate; the difference between them is being made in the tank.

There are quite a few reasons why tank nitrate can rise. They include:
Too many fish - the more fish the more ammonia they excrete which is turned into nitrate
Overfeeding - uneaten food decomposes to make make ammonia which is turned into nitrate
Water changes not often enough or not big enough - nitrate not removed so it builds up
Substrate not cleaned properly - uneaten food and fish poo decomposes to make ammonia which is turned into nitrate
Filter not cleaned often enough - the brown goo is uneaten food, fish poo etc which decomposes to make ammonia etc.

Your tank is not really overstocked so we can rule out #1. But 30 litres a week water change isn't really enough - you need to change at least 55 litres. And the others may also contribute.

But nitrate is a slow killer so that shouldn't be causing your current problems,, just something to bear in mind long term.

Which species of gourami are they? Dwarf gouramis are known to have health issues.
How long before the deaths did you get the new fish?

 

[Raws69]

Gourami's were indeed blue dwarf (1 male, 2 female). The male lasted 2 weeks. The guppies however are mixed of 6 weeks in the tank to 4 days in the tank.

from what I’ve read about gourami disease (after I bought them) the fish didn’t show the common symptoms. Also can this transfer to another fish?