% water change after cycling?

KingBrian

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After the nitrogen cycle is completed, and my nitrates are off the charts can I just go straight and do it like a 90% water change and not disrupt the beneficial bacteria? The last nano tank that I cycled. I ended up having to do a couple of 50% water changes a few days in between because of high nitrates. I just wanna make sure I can just go straight and do a large water change since most of the bacteria will be in the sand bed and the live rock.
 
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Sure, I don’t like to change any parameter to fast. But that’s just me. I don’t see a need to go from day 50ppm to say 5ppm instantly it usually takes us 3-6 months to stabilize it so no rush.

I would do that with every parameter except MG and CA.

But likely big changes no going to upset anything so just a different approach
It was reading 100 nitrates using salifert tests after I got my cycle down to less than 24 hours. I went a couple weeks like that high but I didn’t have livestock in it so it wasn’t a worry. But wanted to add 2 clowns and wasnt going to add them that high. I did like a 40% water change and the nitrate came down to 60 ish and so did another 40-50% water change a week later and it came down to 15 so I left...

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After the nitrogen cycle is completed, and my nitrates are off the charts can I just go straight and do it like a 90% water change and not disrupt the beneficial bacteria? Get ready to cycle a nano tank and the nano tank that I did. I ended up having to do a couple of 50% water changes a few days in between because of high nitrates. I just wanna make sure I can just go straight and do a large water change since most of the bacteria will be in the sand bed and the live rock.
Well you can but are you sure the nitrite is not interfering with the nitrate test, giving it a false high reading. Depends how you cycled it really.
 
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twentyleagues

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After the nitrogen cycle is completed, and my nitrates are off the charts can I just go straight and do it like a 90% water change and not disrupt the beneficial bacteria? Get ready to cycle a nano tank and the nano tank that I did. I ended up having to do a couple of 50% water changes a few days in between because of high nitrates. I just wanna make sure I can just go straight and do a large water change since most of the bacteria will be in the sand bed and the live rock.
Well you can but are you sure the nitrite is not interfering with the nitrate test, giving it a false high reading. Depends how you cycled it really.
I was wondering this as well. How much ammonia did you add? Nitrate really shouldnt be all that high.
 
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KingBrian

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I was wondering this as well. How much ammonia did you add? Nitrate really shouldnt be all that high.
I use the exact process of Dr Tim’s cycling instructions. My first ammonia dose I was shooting for 2PPM and I got to 1.5 ppm. I dosed per the instructions word for word. At any given time my ammonia never went over 2 ppm. Nitrates are off the charts at the end. I had zero ammonia and zero nitrite at 9 days, and high nitrate. And I’ve seen other people do the same process on YouTube and have the same results with the nitrate off the charts. I used Salifert tests
Well you can but are you sure the nitrite is not interfering with the nitrate test, giving it a false high reading. Depends how you cycled it really.
 
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I would only change enough to lower nitrate by half provided half does not lower below 5ppm.

We need a stable and balanced nitrate number in our system to feed everyone

Brining down slowly is better.
Could I please ask, what is the concern here with bringing the nitrates down too quickly? It doesn’t look like the OP has any nitrites to inflate the nitrates, and the OP really has no livestock outside of some bacteria at this point. I agree with the OP that when using the Dr. Tim’s “system” the nitrates often do end up sky high; I’ve experienced that first hand :-) When in the same situation as the OP, I have always done a large water change after the cycle. Is there something I’m missing or doing wrong? Thank you for your help!
 
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Uncle99

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Could I please ask, what is the concern here with bringing the nitrates down too quickly? It doesn’t look like the OP has any nitrites to inflate the nitrates, and the OP really has no livestock outside of some bacteria at this point. I agree with the OP that when using the Dr. Tim’s “system” the nitrates often do end up sky high; I’ve experienced that first hand :) When in the same situation as the OP, I have always done a large water change after the cycle. Is there something I’m missing or doing wrong? Thank you for your help!
Sure, I don’t like to change any parameter to fast. But that’s just me. I don’t see a need to go from day 50ppm to say 5ppm instantly it usually takes us 3-6 months to stabilize it so no rush.

I would do that with every parameter except MG and CA.

But likely big changes no going to upset anything so just a different approach
 
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Sure, I don’t like to change any parameter to fast. But that’s just me. I don’t see a need to go from day 50ppm to say 5ppm instantly it usually takes us 3-6 months to stabilize it so no rush.

I would do that with every parameter except MG and CA.

But likely big changes no going to upset anything so just a different approach
Thanks for your reply! I am with you 100%, though at this point without livestock I don’t see why not do a large water change, but again, just a different approach :)

Thanks again!
 
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Thanks for your reply! I am with you 100%, though at this point without livestock I don’t see why not do a large water change, but again, just a different approach :)

Thanks again!
My pleasure.

You’re right, probably doesn’t matter much at cycle stage.

What will be important is can you “hold” that low level off the start.

So if I bring a new system online at say 50ppm, and reduce to say 10ppm, mine increases until I have enough processors to hold 10ppm.
 
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twentyleagues

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This seems weird to me and I am not doubting you. You would think dry rock/sand ammonia add starts would be roughly the same regardless of the brand used. My only thought is the bacteria provided differs enough to make a large difference in the amount of nitrates left at the end. I used microbacter xlm and their ammonia product. I dosed to 2.0ppm ammonia 3 times and only had 25ppm nitrate at the end. Now I dont know what you consider high maybe your off the charts is less than 25ppm at 25 ppm I was debating leaving it there as I dont see that as incredibly high. I did a 50% water change anyway. My off the charts would be 50ppm+, Hannahs lr is 75ppm I think. So what exactly is off the charts here? If there is any nitrite left it will read 3-4 times more nitrate.
 
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Randy Holmes-Farley

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I expect nitrate is not high and there is no reason to do any water changes. The nitrate probably just looks high due to nitrite interference.
 
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KingBrian

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Sure, I don’t like to change any parameter to fast. But that’s just me. I don’t see a need to go from day 50ppm to say 5ppm instantly it usually takes us 3-6 months to stabilize it so no rush.

I would do that with every parameter except MG and CA.

But likely big changes no going to upset anything so just a different approach
It was reading 100 nitrates using salifert tests after I got my cycle down to less than 24 hours. I went a couple weeks like that high but I didn’t have livestock in it so it wasn’t a worry. But wanted to add 2 clowns and wasnt going to add them that high. I did like a 40% water change and the nitrate came down to 60 ish and so did another 40-50% water change a week later and it came down to 15 so I left it and added my clowns. Never had an issue after that. It stayed in check with my maintenance and feeding regime. Kept lights off 4 months never had an ugly phase of any kind. So my question was if I end up in that situation again this time, can I just go right to a huge water change if my readings are similar? If that makes sense. This scenario is only if my nitrates are off the color scale again and that may not happen idk yet.
 
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Randy Holmes-Farley

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It was reading 100 nitrates using salifert tests after I got my cycle down to less than 24 hours. I went a couple weeks like that high but I didn’t have livestock in it so it wasn’t a worry. But wanted to add 2 clowns and wasnt going to add them that high. I did like a 40% water change and the nitrate came down to 60 ish and so did another 40-50% water change a week later and it came down to 15 so I left it and added my clowns. Never had an issue after that. It stayed in check with my maintenance and feeding regime. Kept lights off 4 months never had an ugly phase of any kind. So my question was if I end up in that situation again this time, can I just go right to a huge water change if my readings are similar? If that makes sense. This scenario is only if my nitrates are off the color scale again and that may not happen idk yet.

How did you cycle? I’m not understanding how nitrate gets to 100 ppm with most methods of cycling, and I expect it was nitrite interference. If that is the reason, there may have been no reason to change water.

Imo, the old idea of post cycling water change is flawed and based on the idea that nitrate needs to be very low.

The water changes didn’t hurt anything, but may not have been particularly useful.
 
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How did you cycle? I’m not understanding how nitrate gets to 100 ppm with most methods of cycling, and I expect it was nitrite interference. If that is the reason, there may have been no reason to change water.

Imo, the old idea of post cycling water change is flawed and based on the idea that nitrate needs to be very low.

The water changes didn’t hurt anything, but may not have been particularly useful.
Nitrite had been at zero as well as ammonia for a time. I always tested nitrite as well. It got that high from Dr Tim’s method. Nitrifying bacteria and ammonium chloride method per the instructions. After the cycle was finished I dosed ammonium chloride again and it cleared ammonia and nitrite in 24 hours, less actually. After that my nitrates were that high and ammonia and nitrite never showed up again. I researched others who had nitrates off the color chart when they were done with the cycle and nitrite was zero using that method. I get what you’re saying if the nitrites registered would have affected the nitrate number. After 2 large water changes Nitrate was at 15, amm and nitrite zero. That seemed reasonable and not too low. I verified it with more tests.
 
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Ben's Pico Reefing

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Like others said something is off. But you can do as big or small water change as you want and comfortable with. Remember this isn't really about the cycle. It's about establishing the bacteria. Since bacteria live on surface areas, it will not effect them as long as you don't dry them out.

Why I'm also not a fan of using ammonia to cycle vs using live rock and coral or bottle bacteria right away. It does work with great success. But causes a lot of confusion about "stall cycling" or cycling gone wrong which really hasn't gone wrong.

On the other hand dosing ammonia to cycle teaches patients and does help understand a bit better what is really going on. We see threads like this almost hourly and everyone is great to respond. There are sometimes multiple answers for the same solution.
 
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