Fish keep dying in two tanks.

[IFLAquatics]

I would purchase an API freshwater master test kit when you get the funds. This is a liquid test and way more accurate than test strips. Test your tap water, and test your tank. If you are doing enough water changes, the water from the tank and tap shouldn't very by much. PH from the tap should be tested after sitting out for 24 hours. Check your water quality reports, which is done yearly, for information on the general hardness of your water, as well as buffering capacity. You could also purchased a API GH/KH test kit and test the water yourself since the water report doesn't provide daily information, just an average for the year across different locations. A nice to have, but not necessary, is a total dissolved solid meter. Once you get a handle on how dirty your tank water becomes over the course of a week, you can use the TDS meter to do a quick check of when you need to do a water change.

Thats really cool lol. I love chemistry so i have no problem diving into all the facts about the chemical levels and having to use the test kits and everything. I am definitely getting a master test kit, i didnt realize how dangerous the buildup underneath was and how bad it really was under there either or that when i move the sand it does that. I also had a large crawfish in there and they hoard food under rocks and in the skull deco she lived in and that adds to the decaying smell. Im also going to look into the TDS because that sounds like a good way to track and monitor their levels rather than dip tests.

 

[IFLAquatics]

Very low pH can be caused by lack of maintenance. The pH in a tank will drop as the water condition gets poorer. You may be right that low pH is a problem, but the pH is probably low because of the poor maintenance.
Also the "test strips" are pretty worthless, I would recommend you get a liquid kit. The strips are pretty inaccurate.
Also the hardness is not the type of thing that there is really a "safe zone" for per se. Some fish like hard water, some like soft. African cichlids like rock hard, SA cichlids like soft, for example.
I don't believe I actually said anything rude, but I also think you are taking the constructive criticism well.
I get that you are new to the hobby and it's good you are asking questions. It is fairly obvious that the problem you are having is due to poor maintenance. So I am hoping to let you know. The general consensus of succesful fishkeepers, is that at least once a week you need to maintain the tank. How much water you take out will depend on a few factors, like the stocking level, and filtration of the tank. On a 75 gallon tank with large fish like a 12" bichir and large common pleco (waste factory) I would be doing more like 60% every week, or 2x 40% a week. If you can do that, great. If not, you will probably keep having the same problems and keep killing fish.

And no i dont feel you were being rude but the other aspect of that is when people say im not trying to be rude, its either going to be rude, or an opinion that can be construed as rude (AKA criticism in any form) 9 times out of 10. I do appreciate the feedback and i am going to start testing my water also and get my levels back to par. For the most part we havent had any problems but after 4 years of running and only an ich outbreak, we are having issues with the 75 this year. Im new to it and my girlfriend has been doing it a while. I know the hardness is just a preference, i learned that when i freaked out from looking at a test strip and it was almost red in the box. And really i knew it was the maintenence, but i wasnt sure exactly what was doing it becaude i couldnt figure out what the murky but clear and almost gooey look the water got to it. And my comment about the low ph is due to the fact that it will also plummet if you stir the sand and there is alot in it. I feel like with the symptoms i had yesterday i should have waited at least 24 hours before reintroducing them because the water looks completely different today and smells completely different. I feel like the water is honestly safe now. I will be cleaning and testing still though. Another question, while im cleaning the tank next time, no fish, and i stir up all that crud, should i be testing it after each stirring so that i know if the sand is still holding that nasty in it? Because my hypothesis, and correct me if im wrong, is that testing it right after stirring and draining some of it, should show reflections of the spikes in levels if i time it properly. I should be able to stir it, let it settle for a few seconds and then test it i think. Once my levels are no longer spiking when i stir it, it should mean the substrate is clean, right?

 

[Rocksor]

You may or may not get spikes in ammonia (from left over crud in the sand grains) since you've basically started over.

 

[Gourami Swami]

And no i dont feel you were being rude but the other aspect of that is when people say im not trying to be rude, its either going to be rude, or an opinion that can be construed as rude (AKA criticism in any form) 9 times out of 10. I do appreciate the feedback and i am going to start testing my water also and get my levels back to par. For the most part we havent had any problems but after 4 years of running and only an ich outbreak, we are having issues with the 75 this year. Im new to it and my girlfriend has been doing it a while. I know the hardness is just a preference, i learned that when i freaked out from looking at a test strip and it was almost red in the box. And really i knew it was the maintenence, but i wasnt sure exactly what was doing it becaude i couldnt figure out what the murky but clear and almost gooey look the water got to it. And my comment about the low ph is due to the fact that it will also plummet if you stir the sand and there is alot in it. I feel like with the symptoms i had yesterday i should have waited at least 24 hours before reintroducing them because the water looks completely different today and smells completely different. I feel like the water is honestly safe now. I will be cleaning and testing still though. Another question, while im cleaning the tank next time, no fish, and i stir up all that crud, should i be testing it after each stirring so that i know if the sand is still holding that nasty in it? Because my hypothesis, and correct me if im wrong, is that testing it right after stirring and draining some of it, should show reflections of the spikes in levels if i time it properly. I should be able to stir it, let it settle for a few seconds and then test it i think. Once my levels are no longer spiking when i stir it, it should mean the substrate is clean, right?

The key is to not let it get full of gunk in the first place. You shouldn't remove your fish to do the water change. You shouldn't stir and then let it settle, there shouldn't be much to stir. I would just test the water before the change, and then a few hours after. Ammonia, nitrite need to be 0, or the bacterial cycle isn't working. Nitrate should be between 0-20ppm. If nitrates are high, that is an indication that the tank isn't getting cleaned often enough, and that other chemicals and hormones are probably thick in the water.
You are correct that the pH will drop if the substrate is full of crap and then it gets stirred up. But at the end of the day, a tank that is full of crap, is not a healthy environment for the fish, and you will keep having the same problem.
What I would do, is do a very thorough cleaning. Get it perfect. Change the substrate out if you have to. Then do weekly water changes, where you vacuum the gravel.

 

[IFLAquatics]

You may or may not get spikes in ammonia (from left over crud in the sand grains) since you've basically started over.

Alright. Well i guess i will see this week when i get my kit. The bichir is still semi blind(more than usual) from the clouding in his eyes but hes breathing properly again and his slime coat isnt ridiculous. Its gonna take a little time for the eyes i feel. But he isnt being picked on and hes not able to get the cichlids yet so he is safe for the moment. They just got a decent water change.

 

[IFLAquatics]

The key is to not let it get full of gunk in the first place. You shouldn't remove your fish to do the water change. You shouldn't stir and then let it settle, there shouldn't be much to stir. I would just test the water before the change, and then a few hours after. Ammonia, nitrite need to be 0, or the bacterial cycle isn't working. Nitrate should be between 0-20ppm. If nitrates are high, that is an indication that the tank isn't getting cleaned often enough, and that other chemicals and hormones are probably thick in the water.
You are correct that the pH will drop if the substrate is full of crap and then it gets stirred up. But at the end of the day, a tank that is full of crap, is not a healthy environment for the fish, and you will keep having the same problem.
What I would do, is do a very thorough cleaning. Get it perfect. Change the substrate out if you have to. Then do weekly water changes, where you vacuum the gravel.

AndAnd i understand that. But thats already a fact so telling me twenty five times in each post that i need to not let the water get like that in the first place is just pointless. I get that. What i am looking for is solutions, not being told my water is dirty and i dont take good enough care of my tanks. That is useless and that is being over opinionated rather than constructively critical. Now you are starting to be rude. Thank you for your facts but can you please keep your judging and shaming and reminders of how dirty it is and this "its dirty so thats why its dirty and the dirt is dirty and causing dirty water and your dirty fish are dying because of your dirty water" to yourself. Like i said. Constructive criticism i can take, people shaming me for falling behind in every message they send to me is just annoying. Be helpful not hateful.

 

[IFLAquatics]

The key is to not let it get full of gunk in the first place. You shouldn't remove your fish to do the water change. You shouldn't stir and then let it settle, there shouldn't be much to stir. I would just test the water before the change, and then a few hours after. Ammonia, nitrite need to be 0, or the bacterial cycle isn't working. Nitrate should be between 0-20ppm. If nitrates are high, that is an indication that the tank isn't getting cleaned often enough, and that other chemicals and hormones are probably thick in the water.
You are correct that the pH will drop if the substrate is full of crap and then it gets stirred up. But at the end of the day, a tank that is full of crap, is not a healthy environment for the fish, and you will keep having the same problem.
What I would do, is do a very thorough cleaning. Get it perfect. Change the substrate out if you have to. Then do weekly water changes, where you vacuum the gravel.

And to further this conversation in an intelligent and collaborative way, i believe you misunderstand. There are no fish in that tank so i am stirring to get it picked up and cleaned out and then filling it and then repeating this process over the course of two weeks probably

 

[Gourami Swami]

AndAnd i understand that. But thats already a fact so telling me twenty five times in each post that i need to not let the water get like that in the first place is just pointless. I get that. What i am looking for is solutions, not being told my water is dirty and i dont take good enough care of my tanks. That is useless and that is being over opinionated rather than constructively critical. Now you are starting to be rude. Thank you for your facts but can you please keep your judging and shaming and reminders of how dirty it is and this "its dirty so thats why its dirty and the dirt is dirty and causing dirty water and your dirty fish are dying because of your dirty water" to yourself. Like i said. Constructive criticism i can take, people shaming me for falling behind in every message they send to me is just annoying. Be helpful not hateful.

Definitely not trying to be hateful man.Sorry if it came off that way. You asked a specific question and I answered it. You asked about how to best go about stirring up the "gunk" in the sand. The answer is that there shouldn't be that much gunk in your sand to stir up, there is no good way to go about it.

 

[IFLAquatics]

Definitely not trying to be hateful man.Sorry if it came off that way. You asked a specific question and I answered it. You asked about how to best go about stirring up the "gunk" in the sand. The answer is that there shouldn't be that much gunk in your sand to stir up, there is no good way to go about it.

Alright. Are there gravel vacs with better suction out there or anything?

 

[Gourami Swami]

And to further this conversation in an intelligent and collaborative way, i believe you misunderstand. There are no fish in that tank so i am stirring to get it picked up and cleaned out and then filling it and then repeating this process over the course of two weeks probably

I did misunderstand, I thought you were asking how to clean tons of gunk from the sub each week with fish in the tank.
If there is no fish in the tank, I would fill and drain the tank a few times, completely cleaning the substrate each time. If the sand is so full of gunk that you can't get it to look like normal, clean sand after a few cleanings, it might be better to just change it out for new sand. Then once it is cleaned, you are going to have to re-cycle the tank. You can use media from an established filter to skip this process. If you don't know about the nitrogen cycle, definitely read up on that, most important thing to know.
I find that the suction of the hose is dependent on the height. If the end of the hose is much lower than the tank the suction will be stronger. If the tank is low to the ground the suction won't be as strong. A wider tube on the hose can make the water flow faster as well.

edit- also will be pointless for you to test the water while cleaning it now with no fish. Goal should be to get the tank re-started with 100% clean substrate and water, so the levels we commonly test for shouldn't come up anyway.