After 7 months of healthy fish, total die-off. Help!

[Aquatony]

Hello everyone.

I haven't posted in some time! You all helped me get my tank set up, Byron especially (hasnt he helped us all!).

So everything was chugging along in my 10 gallon tank stocked with 6 Glowlight Tetra, 2 Albino Cory Cat.

Then it was a chain of devestating events. First, my 6 yearold invited some friends over to play feed the fish. So that caused an ammonia spike. Water changes and AmQuel to the rescue and we got the water chemistry back to normal, so I thought... I was pretty diligent with my siphoning the gravel, but I missed the little volcano we have, and I guess that was breeding some nasty stuff.

So, one day, I decide to siphon the volcano, and the water was dark as night! Good, I thought to myself!

Finished the water change.

Next morning, every single Tetra was dead, the Cory cats were still alive (breathing air from the surface a lot).

So I checked the water chemistry. 0 ammonia, 0 nitrites, 5-10 nitrates, 77.5* F temp.

Bizarre.

But I didn't test the pH. So then I tested the pH, holy moly, it was 6.0 (or even lower, my test kit doesn't go below 6!) My tap, de-gassed and conditioned, tests at 7.4! Which is spot on according to the municipality which provides us the water.

So somehow, the water from the tap to the tank is becoming highly acidified. The two Cory cats have since died and I'm at zero fish now, which I suppose, is a good time to get working on this. My wife wants us to buy a bigger tank, 39gal range, but I don't want to do that UNTIL this gets sorted out.

Possible issues? One thing is driftwood we had in there, could've been leeching tannins so I've moved that, and done a 25% water change.

What else can I do? The only living things in the tank right now are plants which more or less seem to be OK.

The fish were very healthy prior to the big die-off. Parameters from municipality if needed:

tds, in ppm, 34-87
Bicarbonate, as CaCO3: 17
Carbonate, as CaCO3: 6
Hardness, as CaCO3 (in grains per gal): 1
Hardness, as CaCO3 (in ppm): 16-21

Post 25% water change, the water sampled in two places, shallow and deep, are still registering 6.0.

Help!

 

[Byron]

From the information in your post #1, I see two possible probables for the sudden fish losses/stress.

First, did you use a dechlorinator (conditioner) at that water change after which all fish died or were gasping at the surface. Chlorine (and chloramine if you have it in the water) burns fish gills quite rapidly. Once or twice I have forgotten the conditioner as I began to refill the tank, but I have the habit of watching the fish and one can see by their reactions/behaviours pretty quickly.

Second, and aside from the above the more likely, is the sudden change from an acidic pH to a basic pH. This would have immediately changed the ammonium into toxic amonia, and at such a level that you would see similar reactions from the fish. How this works: when the pH is on the acidic side (below 7), ammonia changes into ammonium and remains such. Ammonium is basically harmless. Bacteria and plants will take it up. However, if the ammonium is high, as it likely would have been here, and the pH suddenly becomes basic (above 7), the ammonium changes into ammonia rapidly. Fish will now be poisoned. This is why a major water change with basic water is not always advisable in emergencies. One has to know the pH of both tank and tap water beforehand.

The wood is not likely the issue. Tannins are harmless to soft water fish, and unless the wood has some toxin that suddenly leeched out, it would not be causing any of this.

Re the pH long-term. Every aquarium as it matures biologically will be collecting organics. All the fish food, any dead plant (or fish), create organics. As the various bacteria break these down, CO2 is produced and this creates carbonic acid so the pH naturally lowers. This happens in all aquaria, but there are some balances to offset it.

First is the GH and especially KH of the water. The latter buffers the pH, maintaining it fairly stable through the processes. But at some point this can give out, and here the GH and KH are very low [I have the same, even lower actually] so the buffering capacity is very minimal. But that is where regular water changes come in; these help to maintain a more steady pH, though it will still be less than the tap water. Siphoning crud from the substrate, and keeping the filter clean, also help. And not overstocking or overfeeding. The feeding issue was clearly a factor.

There is likely some reason why the pH of the tap water is 7.4 as with such very soft water it would tend to be acidic. The water authority probably adds something [Vancouver does this here] which is not permanent. No need to fuss over this, I just wanted to mention it to explain.

So, going forward, expect the pH to be acidic, and stock only fish that prefer this. Most soft water fish do. I have tanks that are around pH 5 (probably lower, the test only goes down to 5), others remain in the 5's and others in the 6's. Each tank can be different because of the fish load, plants, volume, maintenance, etc. Rather than start fiddling with water parameters, which can cause more harm than good anyway, go slow, and see how the tank settles out by itself. This is much safer, and more likely to have on-going stability with respect to the water chemistry. Monitor pH carefully during water changes and see what happens; you may have no issues normally, or you may have to do smaller changes. Of course, ammonia will not normally be an issue, so this is not as critical as it is in an emergency. My tanks all run below 7 as I said, and my tap is 7.0 to 7.2 and I do 60-70% changes weekly with no problem; the pH after such a massive change only rises by a decimal point if that, because the water is biologically stable in the tanks.

Byron.

 

[Aquatony]

Thanks Byron.

So how long do you think I should go before I add a fish into the tank? The traditional water parameters for a nitrogen cycle check out, so in THEORY on paper, it should be good for new fish, right?

I am so perplexed that a pH of 6 can be, at all, healthy for a fish but I guess I'm using my background in human chemistry as a basis for that thought, which of course is obviously flawed in so far as fish are concerned.

I have siphoned all the crud from the gravel that I can get to, I am concerned about destroying the existing biological filter that lives in the tank though by doing any more water changes.

My water changes, for the life of the tank, had been 10% weekly, with both Amquel and NovAqua added in titration to the volume of water.

I did and always do use AmQuel with water changes of ANY kind.

Basically, where do I go from here, since obviously the nitrogen cycle is A-OK, and apparently the pH is stable and happy right where it is?

it is worth mentioning, my wife reminds me, that on the night of the big die-off, the house smelled of sulfur.

 

[Byron]

So how long do you think I should go before I add a fish into the tank? The traditional water parameters for a nitrogen cycle check out, so in THEORY on paper, it should be good for new fish, right?

I have siphoned all the crud from the gravel that I can get to, I am concerned about destroying the existing biological filter that lives in the tank though by doing any more water changes.

Do a thorough cleaning of the substrate, and the filter. If this was what I surmised previously, and not a disease, this is sufficient. It is next to impossible to destroy the biological nitrifying bacteria this way. These tough little critters live on surfaces to which they stick, and you would need to really scrape them off to dislodge them. Water changes...the more the better when things are normal.

I am so perplexed that a pH of 6 can be, at all, healthy for a fish but I guess I'm using my background in human chemistry as a basis for that thought, which of course is obviously flawed in so far as fish are concerned.

Many fish in South America live in water with a pH in the low 4's. Parachierodon axelrodi and P. simulans are two that come to mind. Not all SA fish will manage with this, one has to be species specific.

My water changes, for the life of the tank, had been 10% weekly, with both Amquel and NovAqua added in titration to the volume of water.

I did and always do use AmQuel with water changes of ANY kind.

Increase the water changes to around half the tank; a 10% change is frankly next to useless in a 10g, and this would have contributed to the problem by not keeping the biological system in top shape. You had a decent fish load for such a small tank, and this needs more water changed regularly.

I wouldn't use two conditioners. There is no reason (no benefit), so this means more chemicals are getting inside the fish for no purpose. If the pH remains below 7, you have no ammonia issues. Plants and bacteria will readily take this ammonium up.

 

[Aquatony]

Ah, so maybe not changing enough water at a time, gotcha. I will increase the amount changed.

Would you therefore recommend using just AmQuel going forward?

My son and I have thoroughly cleaned the gravel.

Do you think this would be ready for a fish addition in the next couple days? My normal process of adding fish is...

Open the bag they came in and float it in the tank for 15-20 minutes. Then pour a bit of water from that bag into a separate container, and add about 4oz of water from our aquarium into fish bag. Wait about 15-20 min, then pour more water into the separate container, rinse and repeat for about an hour. Then I check temp and pH of the fish bag to make sure it's relatively close to the tank to which they're going into.

Does that seem pretty much in keeping with best practices? Some of my other fish keeping friends think I'm crazy.

I am looking forward to a larger tank though for sure. 39 gallons should be a lot more fun than the extremely limiting 10g. The 10g will probably eventually become a fancy Betta tank.

 

[Byron]

Would you therefore recommend using just AmQuel going forward?

No, if this were me. I would use the NovAqua alone. I have looked into AmQuel, but I do not like using substances that mess with nature. Ammonia is not a problem, or shouldn't be, in a healthy aquarium. Plants need it, and then there is the bacteria. Adding another chemical to "detoxify" ammonia, when in acidic water it is already detoxified as ammonium, makes no sense to me. And this stuff does get inside fish, and there is no benefit in that.

I used NovAqua for years, but changed to API Tap Water Conditioner because I couldn't get NovAqua in large jugs (which are much less expensive per volume).

Do you think this would be ready for a fish addition in the next couple days? My normal process of adding fish is...

Open the bag they came in and float it in the tank for 15-20 minutes. Then pour a bit of water from that bag into a separate container, and add about 4oz of water from our aquarium into fish bag. Wait about 15-20 min, then pour more water into the separate container, rinse and repeat for about an hour. Then I check temp and pH of the fish bag to make sure it's relatively close to the tank to which they're going into.

Does that seem pretty much in keeping with best practices? Some of my other fish keeping friends think I'm crazy.

I do much the same. I assume you net the fish out of the bag at the end. Don't pour the bag water into the aquarium, it has ammonia and pathogens you don't want.

Byron.

 

[Aquatony]

I do net the fish out of the bag, yes. I feel like my method might introduce some stress to their lives... But I'm not really sure any other way to do it. Usually with the help of my kiddo, I pour the bag slowly into a bucket with the net over the top. I catch the fish in the net and quickly but gently place the net into the aquarium.

I don't have a very fancy method for any of this as I'm not even one year into it. I will probably stick to NovAqua since the amount is not a concern to me, simply conditioning 10 gallons. Maybe if I had a larger tank or several, like you! It would be much more of a cost concern.

I always thought conventional wisdom was to go for zero ammonia. So if my tubes tell me it's slightly less than zero (not perfectly yellow) then I shouldn't be worried?

 

[Byron]

I do net the fish out of the bag, yes. I feel like my method might introduce some stress to their lives... But I'm not really sure any other way to do it. Usually with the help of my kiddo, I pour the bag slowly into a bucket with the net over the top. I catch the fish in the net and quickly but gently place the net into the aquarium.

I don't have a very fancy method for any of this as I'm not even one year into it. I will probably stick to NovAqua since the amount is not a concern to me, simply conditioning 10 gallons. Maybe if I had a larger tank or several, like you! It would be much more of a cost concern.

I always thought conventional wisdom was to go for zero ammonia. So if my tubes tell me it's slightly less than zero (not perfectly yellow) then I shouldn't be worried?

One should be concerned over ammonia or nitrite above zero, certainly. But our test kits, even the best, are not all that scientifically accurate. And with live plants, especially fast growing ones, you should never have ammonia if the tank is not overstocked, maintenance is regular, fish are not overfed, and the species when more than one are suited to each other and the tank size and environment. This is the great benefit of floating plants which is why I have them in every tank.

Also keep in mind that so long as you have an acidic pH the ammonia is primarily ammonium and this is harmless.

 

[Aquatony]

Thanks, Byron.

While I have you, and on the topic of plants, I have a couple of aquatic plants from Petco (the snail free kind) as I delve into planting tanks also.

I attached a photo of what I believe is one of my Amazon swords (I could do a better job keeping track of these). It went from a lush green to this dismal brown very rapidly, and also has this fuzz growing on it (mold...?) I treat with Flourish Comprehensive tabs, under the gravel, near the plant site.

I worry my gravel is too large, and that the nutrients are perhaps not getting to the root? I also am concerned the lighting is sub-par. It is a standard Marineland 2-stage LED light:

https://www.petsmart.com/fish/suppl...wheel-led-aquarium-kit-17298.html?cgid=300002

The system is down 4 LEDs. The LED light, to the naked eye, still looks good,and it's in a room with moderate non-direct lighting.

I am doing a lot to learn this hobby in the 10 gallon, so when I get a larger tank, I don't just magnify the problems.

Final question. With my water parameters such as they are, would a Betta splendens work out? I am concerned about the water current, as I have an airstone as well as the Biowheel 75 (75 Gal/hr). My son is really smitten with Bettas but is also really into the airstone, which does create current a lot of water flow in tandem w/ the Biowheel feed.

Thanks again for all of your help.

 

[Byron]

Thanks, Byron.

While I have you, and on the topic of plants, I have a couple of aquatic plants from Petco (the snail free kind) as I delve into planting tanks also.

I attached a photo of what I believe is one of my Amazon swords (I could do a better job keeping track of these). It went from a lush green to this dismal brown very rapidly, and also has this fuzz growing on it (mold...?) I treat with Flourish Comprehensive tabs, under the gravel, near the plant site.

I worry my gravel is too large, and that the nutrients are perhaps not getting to the root? I also am concerned the lighting is sub-par. It is a standard Marineland 2-stage LED light:

https://www.petsmart.com/fish/suppl...wheel-led-aquarium-kit-17298.html?cgid=300002

The system is down 4 LEDs. The LED light, to the naked eye, still looks good,and it's in a room with moderate non-direct lighting.

I am doing a lot to learn this hobby in the 10 gallon, so when I get a larger tank, I don't just magnify the problems.

Final question. With my water parameters such as they are, would a Betta splendens work out? I am concerned about the water current, as I have an airstone as well as the Biowheel 75 (75 Gal/hr). My son is really smitten with Bettas but is also really into the airstone, which does create current a lot of water flow in tandem w/ the Biowheel feed.

Thanks again for all of your help.

First on the plant species, that is not an Amazon sword [Echinodorus species]. It is nothing I recognize, and I would suggest it is almost certainly some terrestrial plant. It is unfortunate that chain stores (especially) will sell these as aquatic. Sometimes they may last a few months, depending upon the species, but in the end most die from being fully submerged permanently. The "fuzz" is likely fungus. I would pull this out immediately and do a good vacuum into the gravel.

On the light, there doesn't seem to be any data on the linked site. But small tanks with LED usually fare better than larger because the light will be somewhat brighter. I would just want to know the spectrum, as many LED are high blue with little or no red in the mix, and red is crucial for photosynthesis.

Plants can grow in almost any substrate, though with gravel you don't want the grains too large as this doesn't provide sufficient density for a good bacterial bed. The photo is a close-up, but if you intend substrate-rooted plants, I would change the gravel to a finer gravel or sand. Alternatively, you could use little pots for substrate-rooted plants, or avoid them altogether and have plants attached to wood or rock like Java Fern, Java Moss, Anubias. And floating plants with dangling roots.

Which brings me to the Betta question. The parameters are fine. But Betta are sedate cruising fish that naturally live in swamps, ditches, ponds and very small streams, so they do not appreciate water currents. And no other fish obviously, they are best alone.

Byron.

 

[Aquatony]

Thank you as always. I removed the plants in question and siphoned the gravel and area very thoroughly.

I have no idea what spectrum the LEDs provide light in. I've asked Marineland to tell me if they can, I won't hold my breath.

For now, how do you normally attach a, say, Java Fern, to driftwood? I have seen them tied to ornamentation in the tank but I don't know what material is used, since everything is so sensitive in the water.

Thank you!!

 

[StandbySetting]

If you can take the wood out, dry the area and use a cyanoacrylate super glue, otherwise you will have to use fishing line, just ensure the rhizome gets plenty of water flow.

 

[Byron]

I personally would not put any glue in a fish tank, that is just me. The easiest method of attaching Java Fern or Anubias to wood or rock is with fishing line or black cotton thread. The thread will disintegrate over time, but I have never heard of this causing issues. Sometimes, depending upon the wood, you can find a crevice to lodge the rhizome in, and that is sufficient. Eventually the fine true roots growing from the rhizome will anchor the plant.

 

[Ccga]

First on the plant species, that is not an Amazon sword [Echinodorus species]. It is nothing I recognize, and I would suggest it is almost certainly some terrestrial plant. It is unfortunate that chain stores (especially) will sell these as aquatic. Sometimes they may last a few months, depending upon the species, but in the end most die from being fully submerged permanently. The "fuzz" is likely fungus. I would pull this out immediately and do a good vacuum into the gravel.

On the light, there doesn't seem to be any data on the linked site. But small tanks with LED usually fare better than larger because the light will be somewhat brighter. I would just want to know the spectrum, as many LED are high blue with little or no red in the mix, and red is crucial for photosynthesis.

Plants can grow in almost any substrate, though with gravel you don't want the grains too large as this doesn't provide sufficient density for a good bacterial bed. The photo is a close-up, but if you intend substrate-rooted plants, I would change the gravel to a finer gravel or sand. Alternatively, you could use little pots for substrate-rooted plants, or avoid them altogether and have plants attached to wood or rock like Java Fern, Java Moss, Anubias. And floating plants with dangling roots.

Which brings me to the Betta question. The parameters are fine. But Betta are sedate cruising fish that naturally live in swamps, ditches, ponds and very small streams, so they do not appreciate water currents. And no other fish obviously, they are best alone.

Byron.

Hi Byron

Please can you tell me what are the best floating plants.

Thanks.

Sent from my SM-G930F using Tapatalk

 

[Byron]

Hi Byron

Please can you tell me what are the best floating plants.

Thanks.

Sent from my SM-G930F using Tapatalk

I prefer the larger true floaters. Small plants like duckweed can be useful at removing organics/nutrients/ammonia, but they can be rather a nuisance in many tanks and have no "substance" to speak of. A slightly larger but still small floating plant is Salvinia; S. natans is sometimes seen, this is a bit smaller than the truly lovely S. molesta which is probably the correct name for the larger species though it may be seen as S. auriculata that will be the same. Salvinia is a small floating fern, the sole genus in the Salviniaceae family. It consists of three leaves, two floating and one modified leaf submerged that may be mistaken for a root; the stem is branching and creeping, bearing hairs but no true roots. The larger S. molesta has a beautiful silvery sage green sheen to the leaves.

Moving on to more substantial plants, Ceratopteris cornuta (Water Sprite) is probably the nicest. This is also a fern, and there are three species, with C. cornuta being the best floating. This plant will spread its fronds (leaves) to cover the surface of any aquarium if allowed to; daughter plants are produced rapidly on alternate fronds so it is easy enough to remove these as new plants during a water change and discard the larger parent plant. I've been doing this for more than 20 years now, all from a single purchased plant, and I have this plant in three or four tanks. Not always easy to find, but well worth it.

Frogbit is another good floater; there are two temperate species that do not do as well in the aquarium as the true tropical species, Limnobium laevigatum, that comes from South America. I bought a very poor decrepit plant that was labelled the Amazon Frogbit some years ago, and it turned out to be one of the temperate species, identified when it flowered shortly thereafter. It has managed in a couple tanks since, though not as well as I expect the true tropical species would, with the continuing heat.

Another similar is Water Lettuce, Pistia stratiotes. Sometimes one sees a "dwarf water lettuce" but this is only small plants of the species, as there is only the one. Interesting roots when it is happy; I have them extending right down to the substrate in a 20g tank.

Some stem plants make good floaters, Brazilian Pennywort (Hydrocotyle leucocephala) being my particular favourite.

Byron.