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Fatal Low Oxygen Emergency-Need Help :(

8K views 18 replies 6 participants last post by  1stAquarium 
#1 ·
Hi everyone this is my first post on this site, I could really use some advice from more experienced fishkeepers!
I have three tropical freshwater aquariums, a 64 litre, a 30 litre, and my newest addition, a 110 litre Juwel Rekord 800 which I set up a few days ago.
I read about 'instantly cycling' aquariums by adding media from established filters to the new filter. The site I read this on said if you do this you can add fish immediately. I was a bit dubious but thought if I kept testing the water for ammonia, nitrites and nitrates, and doing regular water changes anyway it would help. I did this with my 30 litre when I got it 2 or 3 months ago and it worked great, I keep my beautiful male betta in there and he's very happy and active! :)
So I did this again when setting up my 110 litre; I added sections of both carbon and regular brown sponge to the new filter - big mistake!! I had already added my fish to the tank the day before and they were doing fine, the water was clear etc. I realised the next day I had completely forgotten to add the established media so did so immediately. Before adding the sections of sponge, I rinsed them the best I could in aquarium water from my 64 litre tank (which has been set up around 5 months). On switching the filter back on, it spat out a load of cloudy water and that seems to be when the problems started. The tank water went a bit cloudy but the fish seemed fine during the next few hours so I decided to leave them for the time being and went to bed.
When I got up the next morning the water was extremely cloudy and all the fish were gasping for air at the surface. I did a 50% water change and they seemed fine again, so I went to work. My boyfriend text me whilst I was at work saying he had checked the tank, it was really cloudy again and there was a dead sailfin molly and all the fish were gasping for air again, so he'd moved all the fish into the other two tanks (using various breeding boxes etc as temporary measures so the betta was separated and the larger fish didn't eat the numerous guppy fry I am currently keeping in my 64 litre).
Obviously there was a lack of oxygen in the tank but I am not entirely sure why, and want to prevent this from happening again. I have a few ideas as to the cause of lack of oxygen:
- I only have one plant in the 110 litre
- The tank may have been overcrowded
- There may not have been sufficient surface movement
- A combination of these!
Just to give you a bit more information, these are the fish I had in my 110 litre when the problems occured: 5 white cloud mountan minnows, 5 young golden mountain minnows, 6 guppies, 4 mollies (2 balloon, 1 sailfin, 1 dalmation), and 1 small bristlenose catfish. The sailfin unfortunately died.
When I got home from work I emptied the tank completely, took the established bits of sponge out and threw them away, filled the tank with fresh water, used stress zyme and stress coat, left the tank running overnight, and I have just added the 3 remaining mollies as I was concerned my other tanks are going to be very overloaded with the emergency measures!!
Really sorry about the long post, just wanted to supply all relevant information! Hope someone can help.
 
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#2 ·
Hello and welcome to the forum.

110 litres...so that's about 29 gallons?

"Instant cycling" is kind of a misleading term. The bacteria colonizes on every surface in the tank, on the glass, the gravel, rocks, decor and plants, not just in the filter. Using used filter media in a new tank is a great way to "jump start" your cycle. But fish must still be added slowly. This give the bacteria time to catch up and establish itself on every surface.

I think you added too many fish too fast. 21 fish in a newly setup 29 gallon is a heavy bioload. Have you tested for ammonia and nitrite? What kind of filtration are you using in the tank?
 
#4 ·
Thanks for your reply! Yeah around 29 gallons in American terms, about 25g here in England.
It's a Juwel Rekord 800, comes with inbuilt filter so I'm not entirely sure? I tested the cloudy problem water after taking all the fish out and the nitrites and nitrates were quite high. Guess I'll just have to stick with the emergency housing measures for a while, doing regular water changes and introduce the intended inhabitants slowly?
Also, I have just checked on my 3 surviving mollies in the 110 litre. BTW I got all my mollies 2 days ago so there is a chance they could already have been ill, or it could be a result of the oxygen disaster. The male balloon molly has tiny red dots on the top of his body and one of his fins isn't working very well, which is inhibiting his swimming - the other 2 were chasing him around and pecking at him so I have separated him into quite a large breeding net so they can't get to him. Any suggestions as to what may be causing this, or what I can do? Not a good time for my fishes!! :(
 
#5 ·
I agree with jeaninel, this was most likely a nitrification (cycling) issue, not lack of oxygen per say, though symptoms are identical. Ammonia and nitrite are highly toxic to fish and plants, and fish will gasp at the surface when the toxic level is poisoning them. The gills burn and the fish is unable to get oxygen from the water as a result. The partial water change diluted the toxin and relieved the fish.

Until the nitrification bacteria have multiplied sufficient to handle the ammonia and nitrite, a daily partial water change of 50% of the tank may be needed tyo keep ammonia and/or nitrite levels low enough to not kill the fish. These toxins may kill the fish outright if high enough, or if the fish survive, the effect internally can result in health issues down the road that could be linked back to the ammonia or nitrite toxins. Only time will tell on this aspect.

Using Stress Coat and Stress Zyme should help. The latter is a bacterial supplement that API claims will "seed" the bacteria. I have not used this one specifically but I have used others and they do work, if they are pure bacteria as this one claims to be. It still takes time for the bacteria to multiply, so keep a close observation and at any sign of stress do a pwc using a good conditioner (like Stress Coat).

Byron.

P.S. Welcome to the Forum. Unfortunate your first post was a problem, but hopefully it will rectify itself now.
 
#6 ·
Sorry to hear about your molly. Good move separating him so the others can't pick on him. Any chance you can get a pic?
 
#7 ·
The only think you can do now going fwd the next days or maybe weeks:
Test water each day for NO2, NO3 and Ammonia, every time its rising too far do a larger w/c (NO2 below 0.4 NO3 below 50 Ammonia below 1).
Don't do nothing to your filter. Only food & w/c and wait till the tank stabilizes .

Red dot sound like a injury to me w/out seeing it, could have hurt itself on decor, plastic plants, the other guys may have done this. Just keep an eye on it make sure it doesn't get infected.
 
#8 ·
Thanks guys, appreciate the advice.
I will be most definitely keeping a close eye on ammonia, nitrites and nitrates, and doing regular water changes. Plus using the stress coat, and stress zyme to hopefully speed up the cycling process. I have also pointed the filter output tube up towards to surface to create some surface movement and hopefully introduce more dissolved oxygen to the water. I will be getting a lot of plants soon and leaving the light on as much as possible to introduce more oxygen.
The balloon molly is not looking good, he's kind of laying on his right side in a corner of the net and fighting off floating upwards :( it's his right fin which seems to have been injured. I will try to get a decent photo now.
 
#9 ·
You will be directing your efforts to the present issue, and resolving it I believe, but in case I forget it, I hasve some advice on the water movement/oxygen/plants issue you raise here. The following is copied from my response to another post.

Surface disturbance and faster water flow through the tank is detrimental to plant growth (and the latter to many fish too) and there will always be a "battle" going on biologically, as I'll explain below.

The rate of water flow through the filter has an impact on the amount of oxygen drawn into the water, and carbon dioxide (CO2) expelled from the water in what we call the gaseous exchange. Surface disturbance speeds this up, as does higher flow filtration, airstones and bubble effects and powerheads. There are two detrimental issues to this: CO2 which is extremely important for plant growth is driven out of the water faster, and oxygen is brought into the water at levels beyond what is good for the plants. Plants have more difficulty assimilating nutrients when the oxygen level increases. But the more significant aspect is the CO2.

Submerged plants have difficulty obtaining enough CO2 in nature and in the aquarium; this fact is believed by many to be the reason for the inherently slow growth and low productivity of aquatic plants over terrestrial. Further, freshwater emerged plants have been shown to be more than four times more productive that submerged plants. The reason is because CO2 diffuses so slowly in water as opposed to air, and this limits the underwater plant's uptake of CO2 because the CO2 molecules don't contact the leaves quick enough to meet the plant's needs. Aquatic plants have to use enzymes to rapidly capture the CO2. When the CO2 levels in the water become depleted, these enzymes sit idle, so to speak, but the plant still has to provide energy to them. This results in a reduction in photosynthetic efficiency and therefore growth of the plant because energy is being wasted. Thus, any thing that removes CO2 in however small an amount will be detrimental to the plant's growth.

In a natural or low-tech system, the balance between the 17 nutrients (one of which is carbon) and light has to be there; so anything that may impact however slightly can become a critical factor in less success. The one thing we cannot "control" in this type of setup is the CO2, by which I mean that it is entirely dependent upon the fish and biological processes; with light we can control it, in intensity and duration, to balance, as we can with the other macro- and micro-nutrients through fertilization. Plants will photosynthesize up to the factor in least supply. Many have planted tanks that fail because the CO2 is the limiting factor, and algae will take over because it is better able to use carbonates for carbon than most (but not all) plants. The point here is that nothing should be allowed to negatively impact the CO2 in a natural planted aquarium.

The water flow is important for bringing nutrients to the leaves and roots, and keeping the leaves free of sediments. But there has to be a balance so as not to adversely affect the plants ability to assimilate nutrients including carbon from CO2. And surface disturbance in a planted aquarium should always be as little as possible.

Byron.
 
#10 ·
Thanks Byron, I'll keep that in mind when I get more plants. So many pros and cons involved with fishkeeping!
Took some photos of the molly but can't currently find my USB cable to put them on here. I don't think he's going to make it to be honest, he's trying his best but keeps floating round onto his head and so on. I feel awful, the poor things live with me for just a couple of days and I kill them! The female balloon molly is flicking around onto the gravel/decor a bit now too, like the poorly male was doing yesterday :(
 
#11 ·
I'm almost certain this is the effect of the ammonia. At this stage you can't do more than what you now are, but be prepared to lose them; the internal damage which we can't assess is often significant. Many of us have gone through this, we learn from our mistakes. Don't give up. B.
 
#13 ·
I'm sorry to hear all this. Some will make it others won't. You'll get there, don't give up and once your tank is all & truly cycled you can add a few more fish at one time to restock what you've lost now. Just don't get discouraged now, mistakes happen.
 
#14 ·
Thanks Angel, I read your post from a while back saying you felt like giving up, I'm glad you didn't! :)

Speaking of re-stocking, do you think these fish will be okay stocking wise once the tank is fully cycled: 5 white cloud mountain minnows, 5 golden mountain minnows, 6 guppies, 1 BN catfish and 2 mollies assuming they make it?

I am keeping all the guppy fry in my 64 litre along with my 2 cherry barbs which don't even seem to notice them! Then when they get big enough I plan to sell or give them away, I'm just interested to see what they turn out like!

Also I plan to put my 5 neon tetras in with my betta in the 30 litre tank once everyone is in the intended tanks.
 
#15 ·
I think the numbers are fine in the 110 litre, I am more concerned over the 30 litre (7 US g). I had neons in with a betta many years ago now, and the neons began disappearing--into the betta:shock:. I haven't had bettas since, so it may have been the exception, but I'd be careful. B.
 
#16 ·
Yea lol that 55g really tested my patience on just about any imaginable level in the tank world :) The tanks go to the people here who kept supporting me through rough time not to give up on it thou

The minnows & guppys are in the 110l right? Nothing wrong with the stock Was it my pers tank i'd upp the Minnows to 8-10 once the tank is safe, but that's it

Your 64l is super low stocked really with the 3 cherry alone - Amazing there's still people out there not borderline overstocking WOW. You could consider a group of cory's for it?

The 30l will work for the betta, the neon's i'd suggest at least 8.

Another thought/ idea...if your mollies aren't gonna make it: Put the Cherry's in the 110l. Put Betta & a larger school of neons (like 15-20) into the 64l and use the 30l for fry and/ or shrimp? Just a thought :)
 
#17 ·
With that many fish, I'd be checking the water every morning and night, and doing water changes any time there is even traceable amounts of ammonia and/or nitrite. And maybe take extra care not to overfeed the fish to avoid too much waste.

Good luck, and welcome to the forum. And yay for your planted aquarium. I could never go un-planted now.
 
#18 ·
Hmm my neons are very small! Anyone else had problems with neons and bettas? I did buy 7 neons but 2 died within the first two days (one had a damaged fin, the other looked to have been bitten by something at the LFS?!).
Yeah Angel the minnows, guppies etc will be in the 110l once I get it fully cycled. The golden mountain minnows are just a colour variant of the WCMM so all 10 do shoal together and keep displaying to one another etc.
ATM my 64l is very overstocked due to having to take the fish out of the 110l - I currently have all 10 minnows, 2 cherry barbs, 1 BN catfish, 5 neons and around 90 fry in there!! But once everyone moves into the 110l I will just be left with the fry. I like your idea of moving the fry into the 30l and putting the betta and neons into the 64l - I will definitely get more neons once everything is sorted, they are lovely little fish!
Thanks Stephanie! So glad I found this forum! I can't wait to get my 110l all planted up :)
The orange balloon molly was dead when I came down this morning, as I suspected. The other two look fine though! Only other thing that's happened is the betta somehow managed to jump out of the floating plastic breeding box and had a go at the guppies and ripped a couple of tails - I can't wait 'til everyone is living where they're supposed to be!
 
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