Fish dying! Please help!

[krak256]

I'm not sure what's causing my fish to die. I had 6 new harlequins that died and 2 cardinals that have been in my tank for 6 months that died. I never noticed any of the bodies because my shrimp usually eat it or its hidden within my plants.

I just found a cardinal thats laying on its back "panting" really hard. Can anyone please help?

My water paramenters are:
PH: 7.2
Ammonia: between 0 - .25 ppm
Nitrite: .1 ppm
Nitrate: 50 ppm

I know I have a bit of ammonia and nitrite, but it never was a problem before (PH then was 6). But, about a month ago, I added crushed coral to raise my PH. it used to be 6 or even lower. Perhaps the ammonia is getting to be toxic? My other cardinals, guppies, and shrimp seem fine though.

any help is appreciate!!!!

[krak256]

i just did a 20% water change... but my dying cardinal didnt make it through the water change.

hopefully that'll decrease my Nitrate level. is my high nitrate what killed my fish?

[lauraleellbp]

Why are you trying to increase your pH?

My suspicion is that the addition of your "new" harlequin tetras caused a mini-cycle in your tank.

The ammonia and nitrIte readings are very concerning- means something has happened that your N-bacteria are currently not able to cope with your bioload. In a properly cycled tank, there should never be more than 0ppm of either.

Ammonia and nitrIte are always toxic, and cardinal tetras especially are very sensitive to water quality issues.

What are the parameters of your tap water?

I'd recommend making a series of 25% PWC, at least one a day over the next few days and see what happens with your water parameters.

[Blue Ridge Reef]

Ammonia is more toxic in alkaline water. And cardinals are delicate to abrupt changes in water chemistry, and like soft water -exactly the opposite of what crushed coral does. I'd lose the crushed coral if it were my tank, or else go with hard water fish.

[mistergreen]

NYC's water is pretty soft.. I think that's why he added the crushed coral.

How big is your tank?

[Blue Ridge Reef]

Pretty much all tetras do great in soft water -and it sounds like they had been doing well until he added the new batch of fish. The fact they died immediately makes me think they went through a pretty extreme transition. I'd be inclined to test that pH again and ditch the crushed coral, but that's just me.

[lauraleellbp]

FWIW I'd ditch the crushed coral too... unless it's bringing the pH and hardness back in level with the tap water?

I actually feel like until we have tap water readings and get some more questions answered we're still very much in the dark with most advice...

Why would the pH be so low unless the tap water is low? Is there something else going on that we're missing?

Is there CO2 on this tank?

[fishscale]

You shouldn't be trying to keep ammonia and nitrite down, they should be at 0 and stay there. When a tank has been properly cycled and not overstocked, ammonia and nitrite should always be at 0, and you shouldn't have to do maintenance to keep it there. In addition, the nitrate levels are quite high. Do you do water changes often? 50 ppm is a ton, even for a planted tank.

Please give us the following info:

Tank size
Complete stocking list (with numbers)
Any chemicals you have used on the tank
Maintenance routine (how often you do water changes, and what you do it with)
How planted the tank is
Any fertilization or CO2 (I doubt this is the problem)
History of stocking (when you added all the fish you have in the tank)
How long the tank has been running
What filter you have running

[krak256]

Tank size: 29g
Complete stocking list: as of now, 10 cardinals, 1 otto, 2 med guppies, 2 small fry guppys, and maybe 35 RCS?
Any chemicals you have used on the tank: dose excel about twice a week and flourish twice a week. dosing 1/16 of a teaspoon of phosphate and iron every other day(switch every day).
Maintenance routine: water change once a week, 15-20%
How planted the tank is: seems fine. plants are doing well and growing
Any fertilization or CO2: just flourish and excel
History of stocking: most of the fish were added 7 months ago. i bought 6 small harlequins last week and they died soon after
How long the tank has been running: about 7 months
What filter you have running: eheim 2213. took out the carbon and replaced with a bag of crushed coral

I switched up the carbon for crushed coral about 3-4 weeks ago. i dont think i had any deaths, but my PH was so low, about 6 or less.

NYC tap water comes out around a PH of 7 and is VERY soft. my tank water is soft still. i'm honestly not sure what is causing my ph to be so low. i have not vacuumed my floor bed because i dont want to tear up the dwarf sagg im trying to make a carpet out of or suck up shrimp. would that cause it?

other than that, ive asked my LFS, but they keep telling me a lower PH in a planted tank is normal.... even when i started testing my water about 2 months into running my tank, it had the same ammonia/nitrite readings. about .25 for ammonia and .1 for nitrite. but back then, nitrate was about 20ppm. what would cause my nitrate to spike up?

i mainly wanted to bring up my PH so that it would be closer to my tap and so my RCS would be in better range to breed.

i hope this info helps. please let me know if i need to provide any more info.

[lauraleellbp]

It's very odd that your pH is that low, especially if you are not dosing CO2?

Are you sure your test kit is accurate? Not expired, not using strips?

Have you taken your tank water to the LFS to verify your readings?

What substrate are you using, and what media is in your filter?

What are the paramters of your tap water other than pH (ammonia, nitrIte, nitrAte)?

What chemical(s) are you using to treat your tap water?

Was there ever a point that your ammonia and nitrIte reached and stabilized at zero? A 7month old tank is not that old, especially if you've been adding or stock have been reproducing in your tank over that time, always increasing the bioload... it may be that your tank has never fully cycled.

Your carbon was likely part of your biofilter at the point where you removed it, so that may have hurt, plus you probably have lots of mulm buildup contributing to the nitrIte and nitrAte reading...

[krak256]

I'm pretty sure my test kit isn't expired. i have the red sea master kit. for ph, i also have a wardley kit which gives the same reading.

im using flourite as a substrate. my filter media is whatever came with the eheim 2213. i didnt switch anything except for the carbon.

my tap water parameters are:
PH: 7
Ammonia: 0
Nitrite: between .025 and .1
Nitrate: 0

I'm using Prime to condition my water. I honestly cannot recall every testing and having my ammonia read a flat 0. it's come close, but never dead 0. Nitrite has always hung around .1.

Lauralee, would u recommend i put back my carbon and take out the crushed coral? my tank was doing fine with a low ph, i just wanted neutral water and calcium so i could breed RCS.

[lauraleellbp]

Putting back in the same carbon at this point won't help the biofilter, as any N-bacteria in that carbon is long dead since it's been out of the water for a month.

I'm honestly debating on the crushed coral at this point; it's hard to say without being sure what's causing the dropping pH? And the coral is also likely part of your biofilter at this point, since it's been in the tank a month now... With that nitrIte reading I'm thinking you could use all the biofiltration your tank can get ATM.

Have you been checking the kH and gH since adding the coral?

I'm struggling also still with why your tank hasn't properly cycled after 7 months?

Using Prime can give you a "false" ammonia reading if you do the test within 24 hours of using Prime. However, I don't think that nitrIte readings are affected (though I'm not 100% sure on that point; I've never actually used Prime, just read up on it).

I'm still leaning towards thinking that the rasboras caused a minicycle in a tank that never fully cycled.

[waterfaller1]

Sorry for your loss.

[fishscale]

Hmmm, okay. You seem to know what you're doing and you have good equipment and habits. Could it be that the 6 harlequins put your bioload over the edge? It seems kind of unlikely, but just a theory.

[krak256]

is my bioload that high? i dont have that many fish and i thought RCS affect bioload very little.

why wouldnt my tank have cycled if its run this long? seems odd.

lauralee, you think the harlequins caused a mini cycle? does that usually happen? they were quite small, about a centimeter.

fiscale, love your icon. i hope ur a simpsons fan haha.