Please help - my fish are suffering

[Hopelessness]

Tank
What is the water volume of the tank? 75 litres
How long has the tank been running? Since the start of December
Does it have a filter? Yes
Does it have a heater? Yes
What is the water temperature? 76•
What is the entire stocking of this tank? 4 albino corys, 1 female Betta, 2 ghost shrimp

Maintenance
How often do you change the water? Weekly (with food vacuuming sessions to reduce any waste)
How much of the water do you change? 10 - 15%
What do you use to treat your water? Stress coat & bacto start. Recently used ammo lock after a suspected ammonia spike and alkaline buffer because kh/ph/gh levels were minimal.
Do you vacuum the substrate or just the water? I wasn’t fully but have done in the last few weeks

*Parameters - Very Important
Did you cycle your tank before adding fish? Not properly and I know the implications now
What do you use to test the water? API 5 in 1 and NT Labs mini test for ammonia, nitrite and pH
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Ammonia: 6.0
Nitrite: 0
Nitrate:0
pH: 7.0

Feeding
How often do you feed your fish? Twice daily
How much do you feed your fish? Tiny amount, usually enough to be gone in 20 mins, I clear up any waste.
What brand of food do you feed your fish? Hikari
Do you feed frozen? No
Do you feed freeze-dried foods? No

Illness & Symptoms
How long have you had this fish? My Betta 2 weeks, the corys 5 weeks, the ghost shrimp 7 weeks.
How long ago did you first notice these symptoms? 3 weeks
In a few words, can you explain the symptoms? 3 weeks ago I had a suspected ammonia spike which killed my ember eyes and Ghost, my original Betta overnight. I did everything I could to save the rest of the inhabitants, water changed, ammo lock, increased air supply and managed to save my 5 of my 6 corys and shrimp. Both were looking brighter, swimming about, eating, rummaging etc. The water parameters looked good so I bought another Betta and since then it’s gone back downhill. My corys don’t swim about, haven’t been eating properly, were darting to get air again. my Betta had a good week and then stayed in her basket at the top of the tank. Checked the water and my ph, kh and gh had all dropped severely on Sunday and I lost a cory so I added calcium carbonate and a little bit of bicarbonate because I couldn’t get to the shop. Ammonia and nitrite levels were fine. My Betta is now a lot more active but has stress lines and my corys are eating a bit but mostly lying on the sand.
Have you started any treatment for the illness? Only water treatments to raise the hardness and pH. I did add a tiny bit of salt originally because I was told to.
Was your fish physically ill or injured upon purchase? No, but my Betta was stripey, I didn’t know they were stress lines.
How has its behavior and appearance changed, if at all? They don’t swim around. Can’t see any spots or fungus etc.

Explain your emergency situation in detail.
(Please give a clear explanation of what is going on, include details from the beginning of the illness leading up to now)
Before I start I know I didn’t cycle my fish tank properly, please don’t shout at me as I have already been through so much with them and other things (I bought the tank to help with my anxiety and ptsd… it’s not working out well).
I had a beautiful set up where they were all happy, Ghost was letting me hand feed her, I had a ember eyes to watch, my cory was fizzing around and then I increased their number, my shrimp were sitting eating… and then I added almond leaves and fed them live bloodworm as a treat and it all went wrong…
I did a 10% clean Sunday night (3 weeks ago), dug into the sand to get rid of the left over bloodworm, cleaned the dead leaves off the plants, removed my old filter for a new one that I had been cycling for a few days and went to bed, I woke up to them gasping at the top of the tank, I had to euthanise 2, tested the water and there was a slight (below .5 nitrite level and 0.2 ammonia) spike, did a 50% water change, added air to the tank, bought coral as the pH was down and ammo lock. Lost Ghost, my Betta. Treated the tank, put the old filter back in alongside the new one and did 10% cleans every day. Watched them improve and start to swim, I had 5 corys and 2 shrimp. Checked water parameters, everything was good so bought Gregory, the new Betta… liked her stripes and the fact she watched me at Pets@home
Everything seemed good, they were all swimming about for a couple of days, then one morning they‘d stopped and gone back to flitting up to the surface for air and that’s it, pH had dropped to 6.0, kh 0 and gh 30, have no idea why or what I did wrong. I still have coral in the tank so I added a bit more, calcium carbonate and bicarbonate because it was Sunday and I couldn’t get to the shop.
It’s been a week, my levels are slowly rising, I added a little alkaline buffer to try and raise the pH and kh but i don’t know what else to do, they are so unhappy and I’m trying my best. All I do is stare at them and cry… please help me, as I said I suffer from a lot of stuff and I bought these to help me but instead all I seem to have done is hurt them.
I have added photos of my corys, Betta, the state of the plants l, tank set up and the food I feed them.


Include pictures
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[surajk]

I won't shout at you, you already know things are bad. I think you're chasing down too many different parameters by now. Take a deep breath and focus on what's important.

1. ph, Kh and Gh by themselves will not kill your fish. Managing ammonia is what's important right now.
2. What is your ammonia level? You wrote 6 above with 0 nitrates. if you mean 6ppm ammonia, do a 70% water change now, then another 2 hours later. you have to get the ammonia down before anything else.
3. you have zero nitrates with that bioload? either you're not doing the test right, or your filters are not cycled. You will have to do a fish-in cycle with very frequent water changes.
4. DO NOT bring any more fish into the tank until you are very clear this is cycled.

 

[Hopelessness]

I won't shout at you, you already know things are bad. I think you're chasing down too many different parameters by now. Take a deep breath and focus on what's important.

1. ph, Kh and Gh by themselves will not kill your fish. Managing ammonia is what's important right now.
2. What is your ammonia level? You wrote 6 above with 0 nitrates. if you mean 6ppm ammonia, do a 70% water change now, then another 2 hours later. you have to get the ammonia down before anything else.
3. you have zero nitrates with that bioload? either you're not doing the test right, or your filters are not cycled. You will have to do a fish-in cycle with very frequent water changes.
4. DO NOT bring any more fish into the tank until you are very clear this is cycled.

Hi,
Thank you for your reply.
I wrote the wrong number down, my ammonia is around 0 -0.2. I’m not sure where 6.0 came from or how to edit my post.
I’m sorry, I’m typing ahead of thinking but I am following the test instructions to the letter. I have re-done the ammonia and nitrite one and attached photos.
Do I still need to do a 70% water change?
Again, thank you for replying, I appreciate it.
Ps I don’t plan to bring anymore in period, I will be so happy if I can get these ones swimming around!

Tank
What is the water volume of the tank? 75 litres
How long has the tank been running? Since the start of December
Does it have a filter? Yes
Does it have a heater? Yes
What is the water temperature? 76•
What is the entire stocking of this tank? 4 albino corys, 1 female Betta, 2 ghost shrimp

Maintenance
How often do you change the water? Weekly (with food vacuuming sessions to reduce any waste)
How much of the water do you change? 10 - 15%
What do you use to treat your water? Stress coat & bacto start. Recently used ammo lock after a suspected ammonia spike and alkaline buffer because kh/ph/gh levels were minimal.
Do you vacuum the substrate or just the water? I wasn’t fully but have done in the last few weeks

*Parameters - Very Important
Did you cycle your tank before adding fish? Not properly and I know the implications now
What do you use to test the water? API 5 in 1 and NT Labs mini test for ammonia, nitrite and pH
What are your parameters? We need to know the exact numbers, not just “fine” or “safe”.
Ammonia: 6.0
Nitrite: 0
Nitrate:0
pH: 7.0

Feeding
How often do you feed your fish? Twice daily
How much do you feed your fish? Tiny amount, usually enough to be gone in 20 mins, I clear up any waste.
What brand of food do you feed your fish? Hikari
Do you feed frozen? No
Do you feed freeze-dried foods? No

Illness & Symptoms
How long have you had this fish? My Betta 2 weeks, the corys 5 weeks, the ghost shrimp 7 weeks.
How long ago did you first notice these symptoms? 3 weeks
In a few words, can you explain the symptoms? 3 weeks ago I had a suspected ammonia spike which killed my ember eyes and Ghost, my original Betta overnight. I did everything I could to save the rest of the inhabitants, water changed, ammo lock, increased air supply and managed to save my 5 of my 6 corys and shrimp. Both were looking brighter, swimming about, eating, rummaging etc. The water parameters looked good so I bought another Betta and since then it’s gone back downhill. My corys don’t swim about, haven’t been eating properly, were darting to get air again. my Betta had a good week and then stayed in her basket at the top of the tank. Checked the water and my ph, kh and gh had all dropped severely on Sunday and I lost a cory so I added calcium carbonate and a little bit of bicarbonate because I couldn’t get to the shop. Ammonia and nitrite levels were fine. My Betta is now a lot more active but has stress lines and my corys are eating a bit but mostly lying on the sand.
Have you started any treatment for the illness? Only water treatments to raise the hardness and pH. I did add a tiny bit of salt originally because I was told to.
Was your fish physically ill or injured upon purchase? No, but my Betta was stripey, I didn’t know they were stress lines.
How has its behavior and appearance changed, if at all? They don’t swim around. Can’t see any spots or fungus etc.

Explain your emergency situation in detail.
(Please give a clear explanation of what is going on, include details from the beginning of the illness leading up to now)
Before I start I know I didn’t cycle my fish tank properly, please don’t shout at me as I have already been through so much with them and other things (I bought the tank to help with my anxiety and ptsd… it’s not working out well).
I had a beautiful set up where they were all happy, Ghost was letting me hand feed her, I had a ember eyes to watch, my cory was fizzing around and then I increased their number, my shrimp were sitting eating… and then I added almond leaves and fed them live bloodworm as a treat and it all went wrong…
I did a 10% clean Sunday night (3 weeks ago), dug into the sand to get rid of the left over bloodworm, cleaned the dead leaves off the plants, removed my old filter for a new one that I had been cycling for a few days and went to bed, I woke up to them gasping at the top of the tank, I had to euthanise 2, tested the water and there was a slight (below .5 nitrite level and 0.2 ammonia) spike, did a 50% water change, added air to the tank, bought coral as the pH was down and ammo lock. Lost Ghost, my Betta. Treated the tank, put the old filter back in alongside the new one and did 10% cleans every day. Watched them improve and start to swim, I had 5 corys and 2 shrimp. Checked water parameters, everything was good so bought Gregory, the new Betta… liked her stripes and the fact she watched me at Pets@home
Everything seemed good, they were all swimming about for a couple of days, then one morning they‘d stopped and gone back to flitting up to the surface for air and that’s it, pH had dropped to 6.0, kh 0 and gh 30, have no idea why or what I did wrong. I still have coral in the tank so I added a bit more, calcium carbonate and bicarbonate because it was Sunday and I couldn’t get to the shop.
It’s been a week, my levels are slowly rising, I added a little alkaline buffer to try and raise the pH and kh but i don’t know what else to do, they are so unhappy and I’m trying my best. All I do is stare at them and cry… please help me, as I said I suffer from a lot of stuff and I bought these to help me but instead all I seem to have done is hurt them.
I have added photos of my corys, Betta, the state of the plants l, tank set up and the food I feed them.


Include pictures
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

My original post has an error - the ammonia level is between 0.0 & 0.2 not 6.0, not sure where that number came from (guessing because I was flapping whilst typing).
Thanks for reading my post!

 

[surajk]

Ammonia looks fine, nitrite is fine. Are your nitrates still zero? in a cycled tank you should read some nitrate, unless you're not doing the test right. If this is the API test, you need to shake the bottles and test tube really hard. If, for example, your nitrates are really high and you're getting a false zero, a water change will still help that.

What are the amo, ph, kh and gh out of your tap? gh 30 is pretty high.

Could you elaborate on what type of filter you have, and what you meant why you say you did not cycle properly?

 

[Hopelessness]

I have taken a photo of two strips, the one on the left is tank water, the one on the right is water straight from the tap. I’m concerned that maybe these strips aren’t right - I followed the instructions to read the GH & KH straight away and then wait 30 seconds for the rest, so am ordering a master testing kit so that I can use the bottles (it seems odd that the strip readings are so close in colour considering there are 7 fish/shellfish and plants in one). Hopefully the API tests will give me a better reading.

As for my filter, I currently have two running in my tank, I originally had a small internal filter that came with a 25l tank (second hand tank) but then I decided on a new tank instead and it came with an Aquael ASAP internal filter 300, at first I ran the smaller filter because it had already been running, added the new filter in later and cycled it for 3-4 days which I now know wasn’t long enough so now they are both and have been for 3 weeks? The larger filter doesn’t work as well as I hoped and I would like to get just one decent filter but for now I need to get my fish well.
The shop I bought my original fish from advised that cycling a tank for a few days beforehand would be ok and again with the filter so this is why I said it’s not been cycled properly, instead of doing research I went with what they told me (a mistake I won’t make again).

 

[surajk]

I've also been reading about a Ph crash (its never happened for me so its new) , and what I can read says that a cycled filter converting a lot of ammonia, makes the level of ionized hydrogen rise. H+ ions reduce pH. very low pH impacts the filter BB, which then leads to an ammonia spike.

If this is really what's happening, I would clean up the tank, do a gravel vac, clean the filter media gently to remove any debris, remove any plants that are melting. if your tap pH and ammonia is better, a water change will bring your ph back up.

I have taken a photo of two strips, the one on the left is tank water, the one on the right is water straight from the tap. I’m concerned that maybe these strips aren’t right - I followed the instructions to read the GH & KH straight away and then wait 30 seconds for the rest, so am ordering a master testing kit so that I can use the bottles (it seems odd that the strip readings are so close in colour considering there are 7 fish/shellfish and plants in one). Hopefully the API tests will give me a better reading.

the API tests are definitely better than the kit. This doesn't have an ammonia reading though so I'm not sure how clean your tap water is. ph gh and kh all rise from your tap which makes sense since you're adding to the water. your tap looks like about 6.5 which isn't all that bad. But the api tests will tell us for sure. please see my previous post. It might be what's happening to your ph.

As for my filter, I currently have two running in my tank, I originally had a small internal filter that came with a 25l tank (second hand tank) but then I decided on a new tank instead and it came with an Aquael ASAP internal filter 300, at first I ran the smaller filter because it had already been running, added the new filter in later and cycled it for 3-4 days which I now know wasn’t long enough so now they are both and have been for 3 weeks? The larger filter doesn’t work as well as I hoped and I would like to get just one decent filter but for now I need to get my fish well.
The shop I bought my original fish from advised that cycling a tank for a few days beforehand would be ok and again with the filter so this is why I said it’s not been cycled properly, instead of doing research I went with what they told me (a mistake I won’t make again).

never believe the LFS. was the old filter cycled and had it maintained its cycle? i.e was there any fish in the tank that had the old filter? did it dry out before you moved it? If the filter maintained its cycle and you moved it to the new tank, the new tank is cycled. Again, it may not have enough of a BB colony to handle the bioload of the new tank, which would result in an ammonia spike.

 

[Hopelessness]

I've also been reading about a Ph crash (its never happened for me so its new) , and what I can read says that a cycled filter converting a lot of ammonia, makes the level of ionized hydrogen rise. H+ ions reduce pH. very low pH impacts the filter BB, which then leads to an ammonia spike.

If this is really what's happening, I would clean up the tank, do a gravel vac, clean the filter media gently to remove any debris, remove any plants that are melting. if your tap pH and ammonia is better, a water change will bring your ph back up.

the API tests are definitely better than the kit. This doesn't have an ammonia reading though so I'm not sure how clean your tap water is. ph gh and kh all rise from your tap which makes sense since you're adding to the water. your tap looks like about 6.5 which isn't all that bad. But the api tests will tell us for sure. please see my previous post. It might be what's happening to your ph.


never believe the LFS. was the old filter cycled and had it maintained its cycle? i.e was there any fish in the tank that had the old filter? did it dry out before you moved it? If the filter maintained its cycle and you moved it to the new tank, the new tank is cycled. Again, it may not have enough of a BB colony to handle the bioload of the new tank, which would result in an ammonia spike.

Thank you so much for all of the time you’re taking to help me. I really appreciate it.
I’ll reply properly later as I have to take my dad to the dr’s but I wanted to say thanks and acknowledge your reply.

 

[GouramiGirl100]

Hello! Welcome to the forum we are glad to have you. I wanted to say that you are already doing so much better than the majority of fish keepers out there that are dealing with the same because you recognized an issue and asked for help! Fish keeping is a delicate hobby, no one on this forum will shout at you for making mistakes because we all have made mistakes!
Now for some clarifications, your post was very long and I tried to decipher a timeline so apologies if I’m asking questions you’ve already answered. Is this correct: After the death of the initial betta from an ammonia and nitrite spike, your tank appeared healthy and you bought another betta. The tank seemed good until a sudden pH crash?
I would like to know: how are the fish behaving right now? What type of substrate did you use? You said you added almond leaves, how many did you add? What are your water parameters coming straight from your sink/source?
I suggest: buying a liquid test kit like API master kit as the pH on the strips can be incorrect
The good thing is if your pH is really so low any ammonia present is present in a nontoxic form, however from your test tube results it appears 0 ammonia

 

[Hopelessness]

Thank you for your replies. Three of my corys had a little swim around and ate something and the other one joined in eventually so I am leaving a water change etc until tomorrow so that I don’t stress them out. I tested again with the strips and tubes and they are still the same readings so hopefully they will have a peaceful night.
I’ll reply properly tomorrow morning.
Thanks again
Goodnight

 

[SparkyJones]

You don't have KH according to the strips. If you do it's very minimal maybe 1dKH tops.

There's a couple options. But I want to simplify things figuring your a relatively new fish keeper. Even if you're intermediate, it's just not something that gets mentioned often when reading on cycling or from the fish stores.

If you have low to no KH, the tank is never going to cycle. The bacteria need the carbonates to reproduce. They'll use up the KH, stall and die off.
The alkaline boosters are a balancing act between alkaline booster and acid buffer and its usually temporary effects. Unless you have in tank carbonates like crushed coral to maintain the KH as acids get produced from nitrate conversion.

You can't let the pH drop out with the fish you have, between the transport to the store, and the transport to your home and the acclimation, the fish have been stresses and any additional stress may push them over the edge becuase they are run down.
If the fish were established and it happened they could take the ride down and then back up with water changes with them being weak from transportation it will become the "only the strong survive" scenario.

As far as putting something in tank to "buffer" KH once you increase it there's crushed coral, limestone, coral sand (ground coral) any of this can maintain KH as acids are produced in tank so it doesn't get depleted again causing bacteria colony collapse.

As far as raising KH, I only know baking soda. That should be a quarter teaspoon of baking soda to increase KH by 1 degree. About 18 mg/l or 18 ppm. Take it slow just bump it 1 degree per day with the water change of 50%, and miz it in the water change water before adding it, day after day it will slowly rise. When it gets to 4-6 dKH range (nearing the 80ppm color on the test strip) it's just maintaining it on water changes, disolving the backing soda into the new water to be added before its added.

You source water is really low on KH. Whatever you used for an alkaline buffer didn't even get you to 30ppm KH. And will deplete quickly while cycling due to the bacteria using carbonates to reproduce. All of the new biological activity.

Just my opinion on it. There's a few ways to do this, different methods and products. But your KH has to come up in order to get through cycling or it's just not going to complete.

A daily 50% water change likely will keep ammonia down and the minimal KH in your source water replenished. That's another way to go with this, just want to say when fish in cycling it's not a good idea to water change just once a week. Points happen during cycling where ammonia or nitrites really can stack up over a couple days and kill fish.

As far as fish go, until it's cycled, no more animals please. generally speaking it's really safe to cycle a tank with 1 small fish per 10 gallons of water it never gets out of hand and allows you to check on it every day and if needed, make a water change to keep the parameters low until you only see nitrates for the fish you have. . the couple shrimp are negligible ammonia producers. Where you are currently with fish in 20 gallons, makes it harder on you. When it's cycled you can add a fish here or there over time to get it how you want it exactly. Until then, adding fish just makes it harder and harder to stay on top of with water changes.

All of this is just advice based on the information given with the exception of the KH, if the KH runs out, the bacteria can't reproduce and then instead of multiplying they will stall, and then die off without new ones to replace them and never complete cycling. as the cycle progresses and the bacteria multiplies, more KH is used. and what you have in your source water may not be enough to get it to completion.I really do recommend amending the KH up to 4-6 degrees.
1dKH = 17.9 ppm or mg/L. bringing the KH up to 80-100 ppm or mg/L would make this significantly easier to get through cycling although you still have to keep an eye on Ammonia and Nitrites for the next 30 days and water change if necessary, until you are only seeing nitrates on the tests.

Any time you water change and don't bring up the KH of the new water being added you are going to see the KH come down in tank. so unless you check for new source water (maybe from an outside faucet or maybe the house water is on a filter and you can take your fish water before the filter comes into play, or off of the lawn irrigation system maybe) you will have to amend the KH one way or another.
Maybe check an outside faucet for a hose and see if KH is better from there, or if you have irrigation for the grass, that might be off a well with higher GH and KH. GH is pretty low also according to the strip and it came up with your supplementation in tank. I suspect there's a filter somewhere cutting out hardness. The question is if it's the city or it's at your place.

Water changing isn't going to hurt and can only help, but it's a pain.
with fish in cycle a good rule of thumb is "when in doubt, change it out."

 

[Hopelessness]

Sorry for the delay, I haven’t been too well but have appreciated your messages and will reply properly now.
Before I do, had a day and a half of my fish looking like they were happier, swimming and foraging for food, didn’t do a water change, checked the ammonia/nitrite levels etc everything seemed like it was heading the right way. Then did a 25% water change, cleaned the sand, filters and the dead stuff off the plants (all done out of the tank apart from the sand in tank water so as to keep as much bacteria as I could but not stress the fish out too much or disturb too much) added stress coat, bacto start to the filters. Left it for a few hours, did water tests again, readings were fine (still waiting for my API kit to come so that I can test the kh/gh in a clearer way… all of my fish back to being lethargic and flitting up to the surface for air. Yesterday and this morning they were swimming around and eating. I have no idea what I am doing wrong and feel like maybe they would be better with someone who does because all I seem to be doing is stressing them out and making them ill Gregory, my Betta, was showing a bit of colour yesterday but is now paler and very stripey… I don’t want to be the reason they are suffering.
Photo of them before the water change rummaging for food and the water results.

You don't have KH according to the strips. If you do it's very minimal maybe 1dKH tops.

There's a couple options. But I want to simplify things figuring your a relatively new fish keeper. Even if you're intermediate, it's just not something that gets mentioned often when reading on cycling or from the fish stores.

If you have low to no KH, the tank is never going to cycle. The bacteria need the carbonates to reproduce. They'll use up the KH, stall and die off.
The alkaline boosters are a balancing act between alkaline booster and acid buffer and its usually temporary effects. Unless you have in tank carbonates like crushed coral to maintain the KH as acids get produced from nitrate conversion.

You can't let the pH drop out with the fish you have, between the transport to the store, and the transport to your home and the acclimation, the fish have been stresses and any additional stress may push them over the edge becuase they are run down.
If the fish were established and it happened they could take the ride down and then back up with water changes with them being weak from transportation it will become the "only the strong survive" scenario.

As far as putting something in tank to "buffer" KH once you increase it there's crushed coral, limestone, coral sand (ground coral) any of this can maintain KH as acids are produced in tank so it doesn't get depleted again causing bacteria colony collapse.

As far as raising KH, I only know baking soda. That should be a quarter teaspoon of baking soda to increase KH by 1 degree. About 18 mg/l or 18 ppm. Take it slow just bump it 1 degree per day with the water change of 50%, and miz it in the water change water before adding it, day after day it will slowly rise. When it gets to 4-6 dKH range (nearing the 80ppm color on the test strip) it's just maintaining it on water changes, disolving the backing soda into the new water to be added before its added.

You source water is really low on KH. Whatever you used for an alkaline buffer didn't even get you to 30ppm KH. And will deplete quickly while cycling due to the bacteria using carbonates to reproduce. All of the new biological activity.

Just my opinion on it. There's a few ways to do this, different methods and products. But your KH has to come up in order to get through cycling or it's just not going to complete.

A daily 50% water change likely will keep ammonia down and the minimal KH in your source water replenished. That's another way to go with this, just want to say when fish in cycling it's not a good idea to water change just once a week. Points happen during cycling where ammonia or nitrites really can stack up over a couple days and kill fish.

As far as fish go, until it's cycled, no more animals please. generally speaking it's really safe to cycle a tank with 1 small fish per 10 gallons of water it never gets out of hand and allows you to check on it every day and if needed, make a water change to keep the parameters low until you only see nitrates for the fish you have. . the couple shrimp are negligible ammonia producers. Where you are currently with fish in 20 gallons, makes it harder on you. When it's cycled you can add a fish here or there over time to get it how you want it exactly. Until then, adding fish just makes it harder and harder to stay on top of with water changes.

All of this is just advice based on the information given with the exception of the KH, if the KH runs out, the bacteria can't reproduce and then instead of multiplying they will stall, and then die off without new ones to replace them and never complete cycling. as the cycle progresses and the bacteria multiplies, more KH is used. and what you have in your source water may not be enough to get it to completion.I really do recommend amending the KH up to 4-6 degrees.
1dKH = 17.9 ppm or mg/L. bringing the KH up to 80-100 ppm or mg/L would make this significantly easier to get through cycling although you still have to keep an eye on Ammonia and Nitrites for the next 30 days and water change if necessary, until you are only seeing nitrates on the tests.

Any time you water change and don't bring up the KH of the new water being added you are going to see the KH come down in tank. so unless you check for new source water (maybe from an outside faucet or maybe the house water is on a filter and you can take your fish water before the filter comes into play, or off of the lawn irrigation system maybe) you will have to amend the KH one way or another.
Maybe check an outside faucet for a hose and see if KH is better from there, or if you have irrigation for the grass, that might be off a well with higher GH and KH. GH is pretty low also according to the strip and it came up with your supplementation in tank. I suspect there's a filter somewhere cutting out hardness. The question is if it's the city or it's at your place.

Water changing isn't going to hurt and can only help, but it's a pain.
with fish in cycle a good rule of thumb is "when in doubt, change it out."

Thank you for all of this information, I really appreciate it.
I had ordered Seachem equilibrium product to raise the KH but today when changing the tank added some more coral to the sand to gradually increase the levels and some bicarbonate of soda as a more direct change (as soon as the kit gets here I can test the tank, tap and outside tap water but I ran out of strips last night).
Thank you again for your help, there is no worry that I will buy anymore fish, I just want these to be healthy and happy.
Take care

Hello! Welcome to the forum we are glad to have you. I wanted to say that you are already doing so much better than the majority of fish keepers out there that are dealing with the same because you recognized an issue and asked for help! Fish keeping is a delicate hobby, no one on this forum will shout at you for making mistakes because we all have made mistakes!
Now for some clarifications, your post was very long and I tried to decipher a timeline so apologies if I’m asking questions you’ve already answered. Is this correct: After the death of the initial betta from an ammonia and nitrite spike, your tank appeared healthy and you bought another betta. The tank seemed good until a sudden pH crash?
I would like to know: how are the fish behaving right now? What type of substrate did you use? You said you added almond leaves, how many did you add? What are your water parameters coming straight from your sink/source?
I suggest: buying a liquid test kit like API master kit as the pH on the strips can be incorrect
The good thing is if your pH is really so low any ammonia present is present in a nontoxic form, however from your test tube results it appears 0 ammonia

Thank you for this reply, sorry for the delay.
I am currently waiting for my API master kit to arrive.
It was a very long post and confusing, I’ll try and answer your questions but if I miss any please let me know.

My fish had perked up and were swimming around but then I did a water change this morning and they have gone back to being lethargic and going to the surface for air (there are things in the tank to make bubbles and break the surface).

The substrate is black sand https://www.amazon.co.uk/gp/aw/d/B0090ERUT6?psc=1&ref=ppx_pop_mob_b_asin_title

I added two almond leaves (which I boiled and let cool) but only left them in the tank for a couple of days because something didn’t seem right which was just before the “spike” (when the pet shop did a water test they said it was a spike but the numbers were minimal between .2 ammonia and .25 -.5 for nitrite so I am going off what they said).
When my fish started to look brighter and my levels looked ok I bought my Betta because I missed my original one and it all went wrong again and now I think I’m playing roulette with a cycle but hopefully the master kit can tell me more when it gets here.

Thank you for taking to time to reply and to read all of this.

Thank you so much for all of the time you’re taking to help me. I really appreciate it.
I’ll reply properly later as I have to take my dad to the dr’s but I wanted to say thanks and acknowledge your reply.

Hi,
Sorry for the delay, I really do appreciate your help and advice.
Today I did a good clean of the sand, filters, removed the debris and dead plant bits etc. I am waiting for the API kit to arrive so that I can test the tank, tap and outside tap to see how the levels compare.
My pH seems to be climbing but my GH/KH levels seems to be off.
Thank you again for your time.

 

[surajk]

SparkyJones, thanks for that answer. I consider myself intermediate and yet had no idea about BB dependence of carbonates. I've always had decent Kh out the tap and dead coral in the tank (was my first filter media), so I never had a need to go looking for this info and as you said, it doesn't get mentioned much. Or maybe I don't get to call myself intermediate!

So would this be how the chemistry is working in OPs tank? - tap Kh is low, OP adds Kh boosters. Cycle starts working converting ammonia releasing H+ ions, H+ ions deplete Kh. with no buffer, Kh hits zero, pH drops below 6 due to excess free H+ ions, fish begin to suffer from low pH, cycle stalls due to low carbonates and low pH, ammonia spikes, fish die.

When OP changes water, since tap is so low in Kh, the water change actually lowers Kh further, and makes the situation worse.This is why you're recommending adding baking soda to the water change, to bring the Kh up to a safe level.

OP, I am sorry you're in this predicament. I want you to understand that this isn't your fault. And all of us in this hobby have been through hopeless periods and felt guilty for hurting fish. You had no intention of hurting them and you're doing all you can to try and help. Hang in there, it will get better.

 

[Hopelessness]

SparkyJones, thanks for that answer. I consider myself intermediate and yet had no idea about BB dependence of carbonates. I've always had decent Kh out the tap and dead coral in the tank (was my first filter media), so I never had a need to go looking for this info and as you said, it doesn't get mentioned much. Or maybe I don't get to call myself intermediate!

So would this be how the chemistry is working in OPs tank? - tap Kh is low, OP adds Kh boosters. Cycle starts working converting ammonia releasing H+ ions, H+ ions deplete Kh. with no buffer, Kh hits zero, pH drops below 6 due to excess free H+ ions, fish begin to suffer from low pH, cycle stalls due to low carbonates and low pH, ammonia spikes, fish die.

When OP changes water, since tap is so low in Kh, the water change actually lowers Kh further, and makes the situation worse.This is why you're recommending adding baking soda to the water change, to bring the Kh up to a safe level.

OP, I am sorry you're in this predicament. I want you to understand that this isn't your fault. And all of us in this hobby have been through hopeless periods and felt guilty for hurting fish. You had no intention of hurting them and you're doing all you can to try and help. Hang in there, it will get better.

Thanks for your reassuring message. I really do appreciate it, both me and my partner have been staring at the tank willing them to get up and swim or move or eat.

Update:
Last night did a big water change as they were acting like there was no air, even the snails and shrimp were at the top of the tank today went to the pet shop and bought test strips and a master kit (Amazon seem to have lost mine) and had them rest the water as well. My pH is around 7.2, no ammonia or nitrites… no nitrates either. My Kh and Gh are still low but seem to have improved a little. The shop keeper sold me some antibacterial medicine because she said the water is fine so it could be an internal infection. I came home, they were still lethargic and not interested and my Betta was clamped and at the top not moving.
Didn’t put the medicine in because I was scared it would make it worse…
And then this evening all 4 of my corys are swimming around, digging and playing with the new bubbler and Gregory, the Betta, is slightly unclamped (still has stress lines) and examining everything including the shrimp… I’m scared to take a breath and hope but fingers crossed this is the beginning to them getting better ❤️

 

[surajk]

It's good that they're doing better. Use the test kit (not the strips) to test both your tap water and your tank water and post results. Note the instructions for the test kit, especially the nitrate test (which is the hardest to get right). Test again if and when you see a change in fish behaviour. Raise kh slowly with baking soda as SparkyJones said

What I'm hoping to see is some nitrates, that's what will tell us your cycle is at least starting to work. .

When the LFS tested your water, was it the water before or after your water change?

 

[Hopelessness]

So… an update on my little guys!
My levels are looking much better…

Gh 89.5ppm

Kh 71.6ppm

Ph 7.6

Ammonia .0ppm

Nitrite 0ppm

Nitrate 0ppm

My fish and shrimp are behaving a lot more like themselves. Gregory, my Betta, still has stress lines but is a lot more active and unclamped, I’m hoping if the levels stay consistent she’ll relax. I have bought new lighting which is dimmable, made the tank slightly darker and have some new plants that are being treated before going in. I have also bought a piece of driftwood to attach some plants to for when I’m happy the tank has stopped fluctuating to make a more natural hiding and foraging place for my corys.
I can’t thank you enough for all your advice, patience and support.
Thank you ❤️