What's going on in my tank? Dead angel? Krib with cloudy eye?

[azaahp2]

I have a 160L (I think around 55g?) with sand substrate, rocks, caves, driftwood, plants, couple air stones filtered by Aquis1250.

4x sterbai corys
2x kribs
2x gold angels (had 3) - just got them in the last few weeks
about a dozen male guppies including some juveniles

Temp sits around 27C with pH about 7.4-7.6 (same as local tap water). Parameters today are ammonia 0 nitrites 0 nitrates - about 30? colour darker than 20 but not as 'red' as 40 (aqua one strips test).

Yesterday I woke to find a dead angel it had a distended tummy (especially on one side) with one side looking like it had an internal bleed. I asked the previous owner if they'd had anything happen like that before but haven't heard back yet. Can't seem to find any exact description via google... We were away for a couple of days before that so I hadn't noticed any unusual behaviour.

Then today I noticed my krib that spends all it's time hiding... just sitting in the middle of the water column. She has a cloudy eye on one side. Googling suggests an injury which is possible from a fight with the other krib or maybe the angels. Or I have seen the kribs squeezing down the side of my new snail trap which might have some sharp bits poking out from making the holes... but she's definitely not acting her usual self.

So far everyone else is fine...

But... a few weeks ago I had a cory die-off - 4 cories out of 6 died - and I still haven't figured out the reason.

Could this be related? Could there be some nasty underlying thing going on in my tank?

I've only had the tank set up for a few months, although it was second hand and came with the substrate... if I was getting ammonia spikes, wouldn't my parameters at least show nitrites?

Hope I've given enough info without info overload LOL...! Still so much to learn in this game and I'm keen to know if these things are just part and parcel, or if there's something I need to improve.

PS re the angel it could have over-eaten, as they're very greedy - and polish off the food I put down for the cory's as soon as they've finished their own!

 

[FreshyFresh]

When you got the tank a few months ago, how did you establish a nitrogen cycle?

How much water do you change and how often?

Do you have a means to test for ammonia, nitrite and nitrate in PPM?

 

[FJB]

Ditto to the critical questions asked by FF.
In addition, I would say that the overwhelming majority of cases of cloudy eye are caused by poor water quality, with a small minority due to injuries, although they can happen. That, the history of dying cories and the angel, and the readings of nitrate with the strips, altogether suggest that water quality issues are involved.
A cycling of the aquarium may or not have been fully established earlier, but the presence of nitrate probes that it is now. 30-40 nitrate (need to be ascertained with liquid API Master kit) is not low. 40 is too high, 30 is no consolation. Whether one believes how low it should be is immaterial - the fish are dying. More water changes (frequency and/or amount) are needed. The deaths can also due to other additional causes, but water quality is not helping. It seems as if the problems can be solved easily. Good luck!

 

[TwoTankAmin]

There are several reasons for eye issues besides water quality or injury. Both parasites and bacterial infection cause this. I lost a couple of my wild Altum angels to the bacterial infection. I though the initial angel's white eye was injury related. Then over time it developed a bad case of fin rot. When I then noticed a second angels with it's eye going white, I decided there must be more going on than I had thought. I began treating with API Fin and Body Cure. I lost the original sick angel during this treatment and saw minimal improvement in angel #2 while another angel began to get a white area in one of it's eyes.

I switched treatment at the end of the API med and dose a round of Maracyn which is Erythromycin. I lost the second angel but the remaining fish seemed to be OK. One angel still has a small white spot, but it is not spreading.

Without more info, I cannot say with any certainty what is going on in your tank. When many fish are being lost this is not a good sign. it usually means whatever is going on is contagious.Swollen belly can have an assortment of causes ranging from constipation to bacterial and/or parasitic infections.

This problem does not sound like cycling issues. Ammonia burns would be obvious, and nitrite poisoning causes fish to cluster at the surfaces trying to get the oxygen their blood cab no longer carry. Moreover, cycling issues should self correct when they are killing fish. What should happen, assuming dead fish are quickly removed, is that the ammonia production in the tank is dropping with each death and the bacteria should still be multiplying from the excess ammonia and nitrite. This will not apply if the balance starts out with way too many fish and little or no progress yet on cycling. However, it is certainly possible that cycling issues may have exacerbated things.

My best guess would be you have multiple issues and exactly what they are is what determines the treatments which should be used. I cannot suggest anything here because there are too many problems and some you did not provide details that would suggest a reasonable diagnosis. My gut says bacterial issues, but medicating is stressful to fish. Stress weakens their immune system and the ability to fight off things. So it is important that the medication we may use will work and thus justify the additional stress it may cause. All meds are not equal in this respect.

Can you provide any more information of how the corys etc. that died a while ago looked and behaved? Pictures would help as well. Water changes cannot hurt while you try to figure things out. Also please report what and how you are feeding and if the fish are eating. Also are they pooping and how does the poop look?

 

[azaahp2]

Thanks for your replies folks... sorry I said AquaOne test kit, I meant API. pH about 7.4, ammonia 0, nitrites 0, nitrates I'm guess around 30 (darker than 20, lighter than 40)

 

[azaahp2]

I feed a variety - cichlid flakes and sinking shrimp pellets every morning and every other evening. Every other evening I feed either brine shrimp (from frozen), bloodworms (from frozen) or dried tubiflex worms.

I've always been a minimal feeder once per day but after my cory die-off and reading that cories should look 'fat' I stepped up the feeding in case my guppies were getting all the food before the cories got a chance. But since then I've had a snail population explosion so... I guess the extra food wasn't necessary. I still feed twice a day now tho and I find the angels really big eaters compared to all my smaller fish.

 

[azaahp2]

The krib has perked back up and is eating normally. Her eye looks to be improving as well so I'm hoping it was just an injury...

I do about 40-50% water change and gravel vac every 1-2 weeks. Mainly try to do different half of the aquarium each time, and don't clean all the glass at once to maintain good bacteria.

 

[azaahp2]

This tank is my only one on a cannister filter, but the hoses have a lot of gunk in them. I guess they have better suck than built-in filters, but I do wonder why. Is it because of sand substrate (my others are small pebbles) or way too much food or something else....? Rinsing them out with a hose doesn't really remove it, I soaking the spray arm and joiner in bleach last week with my snail trap and it's come out nice and clean - yet to work on the others. Don't know if anyone has any tips here? Could it be anything to do with nitrates being up, or would that need to be from my tank? As they seem to sit up above 20 even with more frequent water changes. The cannister has been rinsed out twice recently, the last time I hunted through all the media to look for dead fish in case that was causing the nitrates to be up but found none, and the cannister was pretty clean.

 

[azaahp2]

Can you provide any more information of how the corys etc. that died a while ago looked and behaved? Pictures would help as well. Water changes cannot hurt while you try to figure things out. Also please report what and how you are feeding and if the fish are eating. Also are they pooping and how does the poop look?

Here is a link to one of the threads I put up trying to get to the bottom of the cory deaths: https://www.aquariacentral.com/foru...-cory-unexplained-deaths.291385/#post-2980880

 

[azaahp2]

As for establishing the nitrogen cycle I have no technical data there. It wasn't done 'properly' at all... I didn't have a test kit then so got the water tested at my LFS about once per week (and only a few times). I don't think I've ever had a positive ammonia/nitrate reading from that tank but the nitrates have varied, although they seem to be sitting fairly consistenly above 20 now. Even right after water change. So I really don't know, but I do know I've never seen any fish acting like there is ammonia present - gasping, rushing to the surface etc. I always test immediately if I get a death and there has never been ammonia or nitrites present... It is planted so that has likely been to my favour here.

Someone can say if they see my errant flaw in the above, but I am more concerned at the possibility of more underlying issues - especially bacteria or parasites. The tank history (substrate) is unknown. I've added fish from about 4 different sources and I always added the water they came with as well - only recently I read to never do that. I know it's my fault... I don't have a quarantine tank... but I am keen to know if there is any way I can figure out if there is something bacterial or parasitic going on... or something else... or a combination LOL!

I definitely put it down to lack of experience (not neglect!) rather than bad luck!

Oh, and the tank is in a well lit area (without direct sun) but has no lights.

I think I've answered all the questions?

I am so grateful for the time you people have taken to give me such in-depth replies so far ?