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We have a 500 gallon tank with about 100 fingerling catfish. The ammonia is in the harmful to dangerous range (I don't have a more specific measuring test). We have lost about 10 or so fish. They are not eating and they surface for air. We have a 4 station aerator driven and have a constantly cycling system. The pH out of the borehole well is about 7 to 7.5. We have added significant amounts of nitrifying bacteria starter but register no nitrites or nitrates. Water temp is a little cool at 65 deg. F. Yesterday we drained the tank to about 100 gallons and refilled to about 300 gallons exchanging some of the water as we went. The ammonia level was better but not great. Is there any natural source of nitrifying bacteria that will help us get the ammonia breaking down? I am in Nigeria, so I don't have access to all the nice commercial stuff and we want villagers to be able to manage a system with locally available resources. If you can't tell we are pretty raw at this and the system is only about 2 weeks old.

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About 8 on the pH on a consistent basis measured using a five-in-1 Micro-Lift (?) test strip and matching the color. Water temp ranges from 72-80 F. Ambient temp right now here is about 75-80 at night and about 90-95 during the day. Tank (plastic tank) is dug into the ground and is in the shade. We add some water every other day due evaporation from a borehole well where the water comes out at about 63 F. My best guess there is we replace about 15% every other day. We have a pretty steady breeze during most of the day so we are probably getting some evaporative cooling which I assume helps keep the water temp from rising too much as it passes through the growing trough. Alkalinity I think has been in the 180 range. (I am not currently at the site where the details are)

RupertofOZ said:
What is your tank pH Brian.. and how are you measuring it ...
I do have a dissolved oxygen meter. I will check the amount in the water, any guideline there? I really don't like test strips, but that's what I have. One strip to measure pH, Alkalinity, hardness, nitrites and nitrates and one to measure ammonia (I will assume that TAN). I feel like trying to match colors knowing what I want to happen influences what I see! We are now at about 26 days, so we will keep trying to keep the ammonia level below 3.0 and pray for bacteria. BTW we had a concrete block in the tank to put the water pump on. I saw somewhere that could be a problem so we removed it.

Kobus Jooste said:

To lump some of your questions together - the bacteria responsible for ammonification and nitrification does not like direct sunlight, and their activity is influenced by many factors, including pH and temperature. Their activity also requires lots of oxygen in the water as they rely on aerobic reactions.  Your temp and pH together will also play a role in the danger level of uniodized ammonia in the water (kits normally measure TAN or total Ammonia nitrogen, which includes two forms of the the chemical - the uniodized form is very toxic.  Typically, with higer temperatures, the bacterial action will be better, and with neutral to slightly alkaline water, the bacteria will perform better.

 

How sensitive are your kits?  Often with test strips, I could not pick those up.  It typically takes around 40 days to cycle if the process worked well (if you were not adding heaps of cultures to speed it up).  The ammonia will trigger the bloom of nitrite-producing bacteria, and the spike in nitrite will in turn trigger the bloom in nitrate-producing bacteria.  If the ammonia is there, and the temperature and pH is not extreme, the rest will follow as the bacteria is everywhere and WILL show up in your system.

Brian Hitchcock said:

I have a bucket that has a filter that is mesh like a heater filter, I would say it is fiberglass. The water from the bucket starts at the top of the growing bed and runs through a gravel media that consists of granite chips. We will change water again tomorrow. Ammonia is better at the moment, but don't see a hint of nitrates or nitrites yet. It is about 4 weeks.

TCLynx said:

What is your filtration Brian?  Is it media beds or raft beds or biofilter?

 

Patience is the biggest thing (cycling is generally best done with a minimal fish load or fishless to reduce stress and fish deaths but no matter how you do it, cycling up takes time, normally 6 weeks under good to average conditions,) keep your water flowing and being filtered as much as possible and the nitrifying bacteria will show up.  Don't feed the fish, and clean out any uneaten feed that you can and hopefully water quality will improve before you loose too many more fish.

The high pH could be very risky in the long run for the health of the fish in the presence of Ammonia in the system, as the amount of unionized ammonia will be very high.  I suggest you get thew pH to 7 or thereabouts if you can.  At pH 8 the bacteria should start acting though - is a bit alkaline but not too high for them.

 

I have attached a set of worksheets that will help with the ammonia, but it is all in degrees Celcius I'm afraid.

 



Brian Hitchcock said:

I do have a dissolved oxygen meter. I will check the amount in the water, any guideline there? I really don't like test strips, but that's what I have. One strip to measure pH, Alkalinity, hardness, nitrites and nitrates and one to measure ammonia (I will assume that TAN). I feel like trying to match colors knowing what I want to happen influences what I see! We are now at about 26 days, so we will keep trying to keep the ammonia level below 3.0 and pray for bacteria. BTW we had a concrete block in the tank to put the water pump on. I saw somewhere that could be a problem so we removed it.

Kobus Jooste said:

To lump some of your questions together - the bacteria responsible for ammonification and nitrification does not like direct sunlight, and their activity is influenced by many factors, including pH and temperature. Their activity also requires lots of oxygen in the water as they rely on aerobic reactions.  Your temp and pH together will also play a role in the danger level of uniodized ammonia in the water (kits normally measure TAN or total Ammonia nitrogen, which includes two forms of the the chemical - the uniodized form is very toxic.  Typically, with higer temperatures, the bacterial action will be better, and with neutral to slightly alkaline water, the bacteria will perform better.

 

How sensitive are your kits?  Often with test strips, I could not pick those up.  It typically takes around 40 days to cycle if the process worked well (if you were not adding heaps of cultures to speed it up).  The ammonia will trigger the bloom of nitrite-producing bacteria, and the spike in nitrite will in turn trigger the bloom in nitrate-producing bacteria.  If the ammonia is there, and the temperature and pH is not extreme, the rest will follow as the bacteria is everywhere and WILL show up in your system.

Brian Hitchcock said:

I have a bucket that has a filter that is mesh like a heater filter, I would say it is fiberglass. The water from the bucket starts at the top of the growing bed and runs through a gravel media that consists of granite chips. We will change water again tomorrow. Ammonia is better at the moment, but don't see a hint of nitrates or nitrites yet. It is about 4 weeks.

TCLynx said:

What is your filtration Brian?  Is it media beds or raft beds or biofilter?

 

Patience is the biggest thing (cycling is generally best done with a minimal fish load or fishless to reduce stress and fish deaths but no matter how you do it, cycling up takes time, normally 6 weeks under good to average conditions,) keep your water flowing and being filtered as much as possible and the nitrifying bacteria will show up.  Don't feed the fish, and clean out any uneaten feed that you can and hopefully water quality will improve before you loose too many more fish.

Attachments:
Thanks for the worksheet. I sure wish that I had stuck with biology in college now! No worries on the temps in C, I'm getting used to it and we do our readings in C. I just use my phone to convert it when I just can't get past thinking like an American.

Kobus Jooste said:

The high pH could be very risky in the long run for the health of the fish in the presence of Ammonia in the system, as the amount of unionized ammonia will be very high.  I suggest you get thew pH to 7 or thereabouts if you can.  At pH 8 the bacteria should start acting though - is a bit alkaline but not too high for them.

 

I have attached a set of worksheets that will help with the ammonia, but it is all in degrees Celcius I'm afraid.

 



Brian Hitchcock said:

I do have a dissolved oxygen meter. I will check the amount in the water, any guideline there? I really don't like test strips, but that's what I have. One strip to measure pH, Alkalinity, hardness, nitrites and nitrates and one to measure ammonia (I will assume that TAN). I feel like trying to match colors knowing what I want to happen influences what I see! We are now at about 26 days, so we will keep trying to keep the ammonia level below 3.0 and pray for bacteria. BTW we had a concrete block in the tank to put the water pump on. I saw somewhere that could be a problem so we removed it.

Kobus Jooste said:

To lump some of your questions together - the bacteria responsible for ammonification and nitrification does not like direct sunlight, and their activity is influenced by many factors, including pH and temperature. Their activity also requires lots of oxygen in the water as they rely on aerobic reactions.  Your temp and pH together will also play a role in the danger level of uniodized ammonia in the water (kits normally measure TAN or total Ammonia nitrogen, which includes two forms of the the chemical - the uniodized form is very toxic.  Typically, with higer temperatures, the bacterial action will be better, and with neutral to slightly alkaline water, the bacteria will perform better.

 

How sensitive are your kits?  Often with test strips, I could not pick those up.  It typically takes around 40 days to cycle if the process worked well (if you were not adding heaps of cultures to speed it up).  The ammonia will trigger the bloom of nitrite-producing bacteria, and the spike in nitrite will in turn trigger the bloom in nitrate-producing bacteria.  If the ammonia is there, and the temperature and pH is not extreme, the rest will follow as the bacteria is everywhere and WILL show up in your system.

Brian Hitchcock said:

I have a bucket that has a filter that is mesh like a heater filter, I would say it is fiberglass. The water from the bucket starts at the top of the growing bed and runs through a gravel media that consists of granite chips. We will change water again tomorrow. Ammonia is better at the moment, but don't see a hint of nitrates or nitrites yet. It is about 4 weeks.

TCLynx said:

What is your filtration Brian?  Is it media beds or raft beds or biofilter?

 

Patience is the biggest thing (cycling is generally best done with a minimal fish load or fishless to reduce stress and fish deaths but no matter how you do it, cycling up takes time, normally 6 weeks under good to average conditions,) keep your water flowing and being filtered as much as possible and the nitrifying bacteria will show up.  Don't feed the fish, and clean out any uneaten feed that you can and hopefully water quality will improve before you loose too many more fish.

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