Cycling a tank - low nitrates

cdstanley0123

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Hi all,

I set up my tank 5 days ago. I used live sand, dry rock and some live rock rubble in the sump. I added a bottle of ATM colony and 2 clownfish.

I have tested 3/4 times a day since i started cycling. I have never detected ammonia or nitrite. My nitrates are fluctuating between 0.5 and 0.75, but are not increasing.

I’m feeding very lightly once a day, I don’t have the skimmer turned on. I do have a filter sock in and a sponge above the return pump.

Am I doing something wrong with such low nitrates?
 
Hi all,

I set up my tank 5 days ago. I used live sand, dry rock and some live rock rubble in the sump. I added a bottle of ATM colony and 2 clownfish.

I have tested 3/4 times a day since i started cycling. I have never detected ammonia or nitrite. My nitrates are fluctuating between 0.5 and 0.75, but are not increasing.

I’m feeding very lightly once a day, I don’t have the skimmer turned on. I do have a filter sock in and a sponge above the return pump.

Am I doing something wrong with such low nitrates?

How are you testing nitrate?

The nitrate might have come with the salt mix.

Seems like normal results for starting an aquarium with live sand and rubble with a low level of ammonia input (two little fish, lightly fed).
 
Hi! We’ve all been there, it is an exciting hobby, but relax :) 5 days is a very short period. Testing 4 times a day is not going to bring you anywhere. Test ammonia everyday and nitrates every 3 days or so…

Just make sure as you added 2 clowns immediately that ammonia stays 0. For the rest just let the tank do its thing for a week or 2. (Don’t mess with it too much) as for the nitrate reading, I don’t know what test you are using but 0,5 or 0,75 (how do you even tell) is negligible and could be testing error.
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
 
Last edited:
Hi all,

I set up my tank 5 days ago. I used live sand, dry rock and some live rock rubble in the sump. I added a bottle of ATM colony and 2 clownfish.

I have tested 3/4 times a day since i started cycling. I have never detected ammonia or nitrite. My nitrates are fluctuating between 0.5 and 0.75, but are not increasing.

I’m feeding very lightly once a day, I don’t have the skimmer turned on. I do have a filter sock in and a sponge above the return pump.

Am I doing something wrong with such low nitrates?

How are you testing nitrate?

The nitrate might have come with the salt mix.

Seems like normal results for starting an aquarium with live sand and rubble with a low level of ammonia input (two little fish, lightly fed).
Hi Dan, thanks for replying.

I’m using the RedSea nitrate test that comes as part of the Algae control Pro pack. Tbh… trying to decide between the colours when the shades are so similar it’s a task in its self!
 
Hi all,

I set up my tank 5 days ago. I used live sand, dry rock and some live rock rubble in the sump. I added a bottle of ATM colony and 2 clownfish.

I have tested 3/4 times a day since i started cycling. I have never detected ammonia or nitrite. My nitrates are fluctuating between 0.5 and 0.75, but are not increasing.

I’m feeding very lightly once a day, I don’t have the skimmer turned on. I do have a filter sock in and a sponge above the return pump.

Am I doing something wrong with such low nitrates?

How are you testing nitrate?

The nitrate might have come with the salt mix.

Seems like normal results for starting an aquarium with live sand and rubble with a low level of ammonia input (two little fish, lightly fed).
I’m using the RedSea nitrate test kit, so totally get that there’s room for user error.. I’m far from a professional at this 🤣🙈
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
 
Hi! We’ve all been there, it is an exciting hobby, but relax :) 5 days is a very short period. Testing 4 times a day is not going to bring you anywhere. Test ammonia everyday and nitrates every 3 days or so…

Just make sure as you added 2 clowns immediately that ammonia stays 0. For the rest just let the tank do its thing for a week or 2. (Don’t mess with it too much) as for the nitrate reading, I don’t know what test you are using but 0,5 or 0,75 (how do you even tell) is negligible and could be testing error.
Haha.. I guess I was excited to get set up and get used to testing the water parameters.

I’m using the RedSea nitrate test kit, so it goes up in increments of 0.25
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
I did the same thing you did, as adding fish immediately was on the instructions of the Fritz turbo 900 that a lot of refers recommend using. I’m on week 3 and my little clownfish are doing great. It’s not an ideal way to cycle the tank, but don’t beat yourself up about it. Just keep a close eye on your ammonia levels and don’t be afraid to ask questions here. There’s a lot of very knowledgeable people here that love the hobby and are eager to help!
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
I did the same thing you did, as adding fish immediately was on the instructions of the Fritz turbo 900 that a lot of refers recommend using. I’m on week 3 and my little clownfish are doing great. It’s not an ideal way to cycle the tank, but don’t beat yourself up about it. Just keep a close eye on your ammonia levels and don’t be afraid to ask questions here. There’s a lot of very knowledgeable people here that love the hobby and are eager to help!
Thanks for your comment. I’m keeping a close eye on the fish and testing way more than I should be, but I’m enjoying getting used to testing, so testing too much can’t be a bad thing 🙈

The fish are really active, seem happy and ammonia is still at 0, so I’ll keep everything crossed for a positive outcome!
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
I did the same thing you did, as adding fish immediately was on the instructions of the Fritz turbo 900 that a lot of refers recommend using. I’m on week 3 and my little clownfish are doing great. It’s not an ideal way to cycle the tank, but don’t beat yourself up about it. Just keep a close eye on your ammonia levels and don’t be afraid to ask questions here. There’s a lot of very knowledgeable people here that love the hobby and are eager to help!
Did you have any blips in your first 3 weeks? Anything I should be looking out for?

I only have a pair of clowns in at the moment. They seem pretty happy so far
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
I did the same thing you did, as adding fish immediately was on the instructions of the Fritz turbo 900 that a lot of refers recommend using. I’m on week 3 and my little clownfish are doing great. It’s not an ideal way to cycle the tank, but don’t beat yourself up about it. Just keep a close eye on your ammonia levels and don’t be afraid to ask questions here. There’s a lot of very knowledgeable people here that love the hobby and are eager to help!
Did you have any blips in your first 3 weeks? Anything I should be looking out for?

I only have a pair of clowns in at the moment. They seem pretty happy so far
I had the little roller coaster of ammonia, nitrite and nitrate that showed the tanks was cycling last week. I did water changes and had a quarantine tank on standby to pull the fish if I needed to, and tested every day, but it equalized pretty quickly. I’ve got a little bit of algae growing now so I added some turbo snails and a peppermint shrimp to my CUC and they’re doing a great job keeping it minimal.
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
I did the same thing you did, as adding fish immediately was on the instructions of the Fritz turbo 900 that a lot of refers recommend using. I’m on week 3 and my little clownfish are doing great. It’s not an ideal way to cycle the tank, but don’t beat yourself up about it. Just keep a close eye on your ammonia levels and don’t be afraid to ask questions here. There’s a lot of very knowledgeable people here that love the hobby and are eager to help!
Did you have any blips in your first 3 weeks? Anything I should be looking out for?

I only have a pair of clowns in at the moment. They seem pretty happy so far
I had the little roller coaster of ammonia, nitrite and nitrate that showed the tanks was cycling last week. I did water changes and had a quarantine tank on standby to pull the fish if I needed to, and tested every day, but it equalized pretty quickly. I’ve got a little bit of algae growing now so I added some turbo snails and a peppermint shrimp to my CUC and they’re doing a great job keeping it minimal.
That’s really good to know! At what point did you add the CUC? I have a RedSea nano with the RedSea 50LED. I have the blues and whites on 1% at the moment, just so I can see the fish and so the tank looks good…

My aim is to add some soft and LPS corals. I want to keep corals more than fish, so I think the clowns will be the only swimmers I’ll be adding
 
You added bacteria but no ammonia? It will take time for the fish to create ammonia which will take time for nitrate to show up. 5 days is too soon for a cycle and really too early for fish IMO. A dry rock cycle takes about 3-4 weeks to complete and only then should fish be added, you've got ways to go.
Thanks for replying. My LFS recommended using ATM Colony and said to add two fish straight away to create the ammonia. But on reflection, after reading a lot of forums I understand this isn’t what most people recommend
I did the same thing you did, as adding fish immediately was on the instructions of the Fritz turbo 900 that a lot of refers recommend using. I’m on week 3 and my little clownfish are doing great. It’s not an ideal way to cycle the tank, but don’t beat yourself up about it. Just keep a close eye on your ammonia levels and don’t be afraid to ask questions here. There’s a lot of very knowledgeable people here that love the hobby and are eager to help!
Did you have any blips in your first 3 weeks? Anything I should be looking out for?

I only have a pair of clowns in at the moment. They seem pretty happy so far
I had the little roller coaster of ammonia, nitrite and nitrate that showed the tanks was cycling last week. I did water changes and had a quarantine tank on standby to pull the fish if I needed to, and tested every day, but it equalized pretty quickly. I’ve got a little bit of algae growing now so I added some turbo snails and a peppermint shrimp to my CUC and they’re doing a great job keeping it minimal.
That’s really good to know! At what point did you add the CUC? I have a RedSea nano with the RedSea 50LED. I have the blues and whites on 1% at the moment, just so I can see the fish and so the tank looks good…

My aim is to add some soft and LPS corals. I want to keep corals more than fish, so I think the clowns will be the only swimmers I’ll be adding
I didn’t add the CUC until I saw the ammonia and nitrites go back down because I didn’t want to risk any other lives with the cycling tank. I had my lights on all day so it was feeding the algae pretty good, but it never got really bad. Picture shows the extent of my algae right when I added the snails and 2 shrimp. Between the 3 snails, two hermits and 2 shrimp, They had it mostly cleaned up by the next day after I left the light off. Ignore the dirty glass 😆
20251117_112235_A40EF32F-CA59-45E3-8DE7-1C35563E791E.png
 
Hi all,

I set up my tank 5 days ago. I used live sand, dry rock and some live rock rubble in the sump. I added a bottle of ATM colony and 2 clownfish.

I have tested 3/4 times a day since i started cycling. I have never detected ammonia or nitrite. My nitrates are fluctuating between 0.5 and 0.75, but are not increasing.

I’m feeding very lightly once a day, I don’t have the skimmer turned on. I do have a filter sock in and a sponge above the return pump.

Am I doing something wrong with such low nitrates?
Hope your aware the fish have to die for cycling to start. In my opinion you did everything wrong. Look up fishless cycling. What you are doing is inhumane
 
Hi all,

I set up my tank 5 days ago. I used live sand, dry rock and some live rock rubble in the sump. I added a bottle of ATM colony and 2 clownfish.

I have tested 3/4 times a day since i started cycling. I have never detected ammonia or nitrite. My nitrates are fluctuating between 0.5 and 0.75, but are not increasing.

I’m feeding very lightly once a day, I don’t have the skimmer turned on. I do have a filter sock in and a sponge above the return pump.

Am I doing something wrong with such low nitrates?
Hope your aware the fish have to die for cycling to start. In my opinion you did everything wrong. Look up fishless cycling. What you are doing is inhumane
Thanks for your reply.

I tested a few hours after I added the fish and so far I’ve never tested any trace of ammonia or nitrite… if you look back on this thread, I’ve been testing multiple times a day.

To my knowledge, the fish don’t have to die to cycle the tank. But I could be wrong on this… but I hope that’s not the case.

If I’ve never tested positive for either ammonia or nitrite… can you let me know what else is impacting the fish? Because I’d want to avoid that if possible

Many thanks, Chris
 
Thanks for your reply.

I tested a few hours after I added the fish and so far I’ve never tested any trace of ammonia or nitrite… if you look back on this thread, I’ve been testing multiple times a day.

To my knowledge, the fish don’t have to die to cycle the tank. But I could be wrong on this… but I hope that’s not the case.

If I’ve never tested positive for either ammonia or nitrite… can you let me know what else is impacting the fish? Because I’d want to avoid that if possible

Many thanks, Chris
An old way of cycling is what you are doing. I cannot answer your Question because I did not go that rout. Others on here do. Some add dead shrimp. That is what creates the ammonia . I would not think the urine from two clowns is enough. I wish I could help. My go to article says they will often die. It also says which jives with my thoughts that it takes longer , as the fishless way ammonia is added to around 4 ppm. It is maintained through the cycle. This took me 45 days to complete
 
Thanks for your reply.

I tested a few hours after I added the fish and so far I’ve never tested any trace of ammonia or nitrite… if you look back on this thread, I’ve been testing multiple times a day.

To my knowledge, the fish don’t have to die to cycle the tank. But I could be wrong on this… but I hope that’s not the case.

If I’ve never tested positive for either ammonia or nitrite… can you let me know what else is impacting the fish? Because I’d want to avoid that if possible

Many thanks, Chris
An old way of cycling is what you are doing. I cannot answer your Question because I did not go that rout. Others on here do. Some add dead shrimp. That is what creates the ammonia . I would not think the urine from two clowns is enough. I wish I could help. My go to article says they will often die. It also says which jives with my thoughts that it takes longer , as the fishless way ammonia is added to around 4 ppm. It is maintained through the cycle. This took me 45 days to complete
I appreciate your feedback. I did add ATM colony that has been around for many years and followed the instructions, which I believe handles most ammonia spikes… it’s been a good few days now and I’m detecting nitrates and no ammonia or nitrites.

Maybe things have moved on since the old way of cycling. Again I could be wrong.

Appreciate your feedback though
 
The fish don't have to die to start the cycle 🙂

Both dead, decomposing organic material (like a piece of shrimp) and living fish create ammonia. Living fish excrete ammonia as part of their normal metabolism.

I hope that helps!
 
The fish don't have to die to start the cycle 🙂

Both dead, decomposing organic material (like a piece of shrimp) and living fish create ammonia. Living fish excrete ammonia as part of their normal metabolism.

I hope that helps!
Thank you for confirming.

To be honest, I already knew the answer, I just didn’t want to get into an argument :)
 

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