Two water changes, numbers remain unchanged - killed my Betta

[Jan Cavalieri]

I received 12 chili raspbora Fry yesterday - I had ordered 4 but they sent 12, but they are all just barely coming out of Fry age. There had been quite a delay because their other Chili Rasboras were showing signs of fin rot so they weren't going to send those, so I really didn't know when to expect them along with some Pleco's I ordered. These Chili Raspboras are 11.99 each - I ordered 4 but they sent 12. All 12 are still alive. I picked this species because they reportedly get along well with Betta and I had one in that 6 gallon tank. When the new fish arrived I realized I really needed to do a water change on the tank - the substrate is large pebbles so I removed those to uncover a HUGE amount of dirt and debris which I quickly suctioned out of there. I replaced the water with fresh declorinated and PH neutralized water (our natural PH is 9.4 which kills off everything so I use a chemical neutralizer to adjust it automatically to 7.0). It works well on my other tanks - with some drifting down due to only having moderate levels of buffering power. Water Hardness i in my tanks are 10.6 making the water moderately hard. KH is 5.3 - a little on the low side. So after I adjust PH I get some drifting down over the course of a week - usually no further than 6.4 to 6.8 - by then it's usually time to do another water change which will bring it back to 7 - which is perfect for all the fish I stock.

Added the Raspbora after a period of temperature acclimation in their bag, as well as dripping in water from the tank into their bag. They did fine. I added them to the aquarium. By this time my Betta is just hanging out in an upper corner of the aquarium. I noticed he seemed terrible stressed from the water change (since he's the only fish in the tank I only do these monthly and it always stresses him out for a day or two). Well this time he died.

I took measurments of the water (this is after a 70% water change and was shocked to discover: Ammonia ,25, Nitrites 2.0, Nitrates at 80 ppm and a pH of 6.8. It occurred to me that this tank never completely cycled, but I had never seen values like this before. So today I did a 50% water change (any more than that and I risked picking up some of the Rasbora fry) and I replaced the water from the cycled tank next to it that currently has perfect water parameters. It seemed to make sense rather than add "from scratch" water - take it from a known perfect source. Well the only parameter that changed was my PH went up to 7 from 6.8 with the first water change. The babies are doing fine, I'm feeding them twice a day but for the life of me I cannot understand why I didn't get SOME drop in NItrites and Nitrates. The Nitrite was is probably what killed the Betta rather than stress, but the Rasbiras all seen to be doing fine.

I'm thinking I should do another 70% water change tomorrow (I'm out of time today) but I simply have no idea why those Nitrites and Nitrates stayed so high after 2 significant water changes. Any ideas? The pebbled bottom on the tank has lots of white stone many of which are now covered in Algae. There is an abundance of snails - but they don't seem to be helping with the Algae situation. With the first water change I removed all the rock because there was a huge pile of dirt on the bottom floor of the tank - so I was able to remove that nearly completely - and I think I must have stirred up some trouble when I did that. It was probably better left alone. But once I removed it - you'd think at least the Nitrates would have dropped considerably even if nothing else changed - no idea where those high numbers are coming from. The tank has a Aquaclear HOB filter with a layer of floss, sponge, carbon and bioballs. - it's perfectly clean and functioning. I also have a thermometer that keeps the water about 78-80 degrees F. It is a 6 gallon tank. I assume all 12 of the Rasbora are still alive - they move too quick to count them!

Any ideas as to what is going on. I'm dreading losing all those Raspora - a small fortune of them, 8 of which were basically gifted to me from the breeder due to the long delay in shipping to ensure I got healthy fish.

 

[itiwhetu]

As you most probably Know I don't like big water changes. 25% is fine once a week. Slowly slowly. When you do big water changes you can get big swings in parameters. Sometimes it works sometimes it doesn't.

 

[Guest14017]

With high nitrites, I've found that water changes do very little to help. I had a nitrite spike at 5 ppm off the charts when I moved my fish to a new tank. None of them ever seemed affected and none died and the levels are back to normal now. I did NOT do large water changes. I added a pretty high amount if salt 3% (I have guppies so this is fine) and I added a little media from my other tank and I basically left the tank alone to catch back up on cycle. I fed less during that time as well. Because my nitrAtes weren't very high, I didn't do excess water changes. Your nitrAtes are high so you do need water changes. When you have a tank with tons of hidden grime and you knock it all loose, it can wreak havoc on your fish and your water quality. You just need to keep up the changes until the nitrAtes come down some. Salt will protect the fish from the nitrite and Prime or another ammonia binder used daily will protect from the low levels of ammonia. Sometimes doing large changes on extremely poor water quality can have a shocking effect on some fish and it's better to get the levels down slowly. It seems to depend on the type of fish.

 

[Jan Cavalieri]

The way I look at it that if I only remove 20% of the water I'm leaving 80% that needs changing due to ph changes, perhaps diseases, high nitrites etc. so I nearly always do big water changes every week on my other tanks - but this little 6 gallon tank had only the Betta in it so I only changed the water about once a month. I don't think this has anything to do with a large water change, the aquarium was filthy. I suspect that once I removed all the stones and suctioned out the thick layer of dirt below it stirred all the dirt up and screwed up the water in my aquarium. The water was originally clear, I was just trying to get rid of the layer of dirt beneath the stones, apparently that was a big mistake. But the betta was freaked out from the minute I started removing stuff from his tank. He and I are normally on very good terms but he wouldn't let me touch him the entire time and just hid in the corner of the tank trying to look small. Then when I stirred up all the dirt with the high nitrite level maybe that was enough to push him over the edge and kill him. Interestingly the nitrites have not affected the 12 Raspdoras in the tank, so I think once all the dirt settled the water quality improved. If I do this again I think I'll remove the fish first or just let the dirt sit at the bottom of the tank. The 50% water change wasn't the problem, it was all the dirt I stirred up when I removed the substrate - since it was pebbles rather than sand or gravel, the dirt didn't settle on top of the substrate like you see with a gravel substrate, instead it sank below the pebbles, not visible - so I probably should have left it alone. My thought at the time was that I suddenly got this shipment of fish so I really should do the water change before I put them in the water - because they are fry size and a water change of any size is going to be very difficult until they get a little bigger. What I NEED to do is retest the water now that any leftover waste I didn't get with the water change may have altered the water chemistry. I also added some more bacteria from Tetra Safe Start Plus to help get this tank cycling since it appears to have lost it's cycling once I stirred up all that dirt. The only thing confusing me is that I've done this before and didn't have any of these problems and the betta was just fine and acted unstressed and normal through out the process. Maybe the addition of the Raspbora after I cleaned the tank and let them acclimate is what really stressed him out and killed him - but I've never had a tank with Nitrites this high - they didn't bother the Raspboras but the Betta is dead - so who knows why the Raspbora could handle the toxic level of nitrites while the betta could not. It just hurt a lot losing him and knowing it probably was my fault, he was very friendly and very smart - one of my favorite fish. I need to make it a priority to retest the water and see if the values are back to normal. Since the water is clear again.

My assistant who cleans my tanks hurt his back and couldn't do water changes for me for a couple of weeks so I've been trying to do them myself - I'm on oxygen and have to take frequent rest breaks so to clean one tank can take me as long as 6 hours. My assistant turned up today and did a beautiful job of water changes, just moved smaller buckets of water so it wouldn't bother his slipped disc as badly. And he did two tanks in 4 hours and I didn't have to do a thing except fight the cable company over my bill for 2 hours on the phone. I hate dealing with cable and sattilite companies - they are so corrupt. I also managed to get my first COVID shot this week - they actually had wheelchairs and somebody pushed me through the whole event so I didn't have to walk through the gigantic event (almost 1 mile of walking) I don't think I would have made it.

 

[mbsqw1d]

Sounds like your setup may have crept down to 6 PH and built up some non toxic ammonium. The water change increased the PH and the ammonium reverted back to ammonia and intoxicated the Betta.

I find small tanks to be less forgiving and everything seems magnified. I somewhat agree that large water changes arent preferable as you could be massively changing water parameters, particularly PH, and shocking the fish.
This is where keeping tanks heavily planted helps us. As itiwhetu states, he does 25% weekly, however this works for him as he has lots of plants to keep on top of the nitrates.
If you have no plants, then the build up of nitrates needs removing, and 25% weekly is insufficient.

The nitrification process produces acid that eats away at the KH and slowly lowers the PH.
With a PH swinging around the 6 - 7 mark, you're dropping in and out of the range where ammonia becomes non-toxic ammonium. You may need to make the decision of whether to keep an acidic tank, or add buffers to keep PH 7+
Either system has its own set of nitrifying bacteria - the lower PH bacteria that process ammonium, and the other that process ammonia.
You might be struggling to maintain a cycle of either type if the PH is moving around.

 

[Jan Cavalieri]

Ok I tested the water today (I haven't done any water changes since the last fatal one). The results were near perfect Ammonia, Nitrites and Nitrates were all zero. The PH was 6.6 and the water level was low = actually the water level was low on all the aquariums so I mized up a new bucket of water with Prime an a Neutralizer/Buffer that has the job of bringing the PH up to 7.0

After adding some of the fresh water and my PH changed just a little from 6.6 to 6.8. I'll take the 6.8 as good enough and test it later in the week - the PH has a habit of getting slowly more acidic as the week progresses. I'll add more of my neutralizer if that occurs and I'll likely get it back to 7.0. i think there was just a lot of particles in the tank still leftover from the water change the last time. It now looks perfectly clear so my test results should be accurate. I do 70% water changes every week on the bigger tanks and i t keeps them looking good too = they both have perfect water parameters with a PH of 7. I think you are correct about little tanks - I need to go easu on the 6 gallon tank with smaller water changes. But that will have to wait until the Raspdora's get just a little bigger and more brightly colored so I can see them. My eyesight is pretty bad - had cataract surgery 3 yrs ago - I think that the surgery made my eyes far worse than they were - I was NOT happy with the result - I can barely see out of one eye and the other eye keeps getting cloudyl I need to make an appointment with him again - it can take months to get in to see once of these doctors and see if I can get the surgery redone (I'm now seeing black specks everywhere) or he can at least give me my correct prescription so I can get the right glasses. Right now I carry a magnifying glass around with me since none of the glasses I have work for me. That really makes me look like an old lady. It will be wonderful to see again. Speaking of old ladies - I just turned 60 in January, unbelievable. I was at the grocery store buying some wine coolers and their sigh states they have to card anybody that looks 30 or younger. Well I GOT CARDED!!!! I realize I had a mask on that makes it hard to tell age, but still I got CARDED! I thanked the cashier for making my day. I know I don't look 60 yrs old and I don't dress like most 60 yr olds either but I certainly look older than 30.

Thanks for everybody's input on this - In the future I'll keep the water changes small for my small tank, I really hate being responsible for the death of a fish.