Aquarium cycle

[saiwong]

This is my first post to this forum, hello everyone.

I kept tropical fish many years (nearly 50 years ago) and interested in starting up the
hobby again. Things have changed since I last kept fish. Never heard of the aquarium cycle
or used any test kits. However, I just did things based on a schedule my dad taught me
(e.g. water changes etc...)

I have now found an old tank and have started an fishless cycle.
I have de-clorinated the water before placing in the tank

I have added bottled ammonia to 2ppm. I am using the NT Labs water test kit to check parameters.
I am trying bottled bacteria. SeaChem Stabilty.

I've set the temperature of the water to 80F.

I followed the steps for using SeaChem Stabilty and nothing much happened for the first few days

on Day 6 the water test results were:
Ammonia 2.0 ppm
Nitrite 0.5 ppm
Nitrate between 5.0 to 10.0 ppm
PH 7
KH 4
GH 6

on the evening of Day 6 I noticed a BACTERIA BLOOM in the tank.

On Day 7 I tested the water parameters
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

I am not sure what was going on. I wonder if the bacteria bloom is the good bacteria from SeaChem Stabilty awakening
and consuming all the ammonia. Not sure why the Nitrate level is at zero ?

I also wondered if I was somehow close to the end of the cycle. So planning to re-dose ammonia to 2.0 ppm
and see if it all gets consumed within 24 hours for the next 3 days.

So I re-dosed ammonia and checked with my water test kit and verified it was 2.0 ppm

This morning (DAY 8) I tested the water and these are the results
Ammonia 2.0 ppm
Nitrite 0 ppm
Nitatrate 0 ppm

Also the bacteria bloom is beginning to clear

So I am wondering if anyone on the forum can clarify what is going on. Has the cycle reset itself ?
Has the bacteria bloom helped or hindered the aquarium cycle ?

 

[Aiken Drum]

You are seeing normal progress for a fishless cycle.

To start with testing kits arent all that accurate, they are good enough for what you are using them for, but a lot of things can throw off test results. Dont expect consistency especially in a newly establishing tank.

What you should be seeing if ammonia and nitrite is being cycled out is nitrate. If you have 2ppm ammonia that should come out as about 7ppm nitrate. Looking at the test chart for NT labs nitrate test, is there really that much difference between 0ppm and 5ppm?

What these products like stability have is bacteria that lives in the water and consumes ammonia. They dont have bacteria that will establish on filter media and actually cycle a tank. Its common to add these products, see good results for a short while, think you are cycled, but if you continue the process it appears to take a backwards step. This is because the bacteria doesn't establish on filter media and just dies off.

Fishless cycle typically takes a couple of months. Every time your ammonia test drops below 1ppm redose it back to 2ppm. Once you can dose 2ppm and 24 hours later see zero ammonia and nitrite you are cycled. I wouldnt even bother testing for nitrate until you are cycled. Weird test results just confuse things and the level of nitrate is just irrelevant.

Biological bloom is normal in an establishing tank. It neither helps or hinders. Its just what happens. Its bacteria feeding on nutrient inbalances and growing in numbers to the point where it is visible. Once things start to settle down it dies off and is a sign of your cycle starting to establish.

 

[saiwong]

Thanks for your reply.
So SeaChem Stability is not really doing anything !

As for the cloudy water, it is slowly beginning to clear. So you say this is the start of the cycle.

I've read and also been told to use different levels of ammonia for the cycle.
(2ppm, 3ppm, 4pmm)

Would using any of these levels be ok ? Are any too low or too high & harmful ?

Is it correct that most of the good bacteria attaches to the filter (approx 90%)
and the rest elsewhere on aquarium surfaces ?
So gravel does not hold much of the good bacteria ?

 

[Aiken Drum]

The general consensus is that those bottled bacteria products don't do much. Ive never personally used stability but from reading threads and reviews on that particular product it doesn't come out well. Ive often seen it referred to as "nitrite in a bottle", with the view that all it is is nitrite. This would speed up your cycle because you usually have to wait for the ammonia to nitrite stage to establish before the nitrite to nitrate stage can begin. If there is nitrite in there to start with the nitrite to nitrate stage can start earlier in the process. Thats just speculation though.

I have had some success with Dr Tims One and Only, and Tetra Safe Start is essentially the same product as they where both developed by the same guy, Dr Tim Hovenec.

Generally cycling out 2ppm is sufficient to moderately stock a tank. Personally because i usually start tanks off slowly and add more fish in gradually i tend to call it a day once its cycling out 1ppm in 24 hours. A moderately stocked tank will be putting in about the equivalent of 0.5ppm ammonia over the course a day, so being able to cycle out 2ppm in a day will remove ammonia before it can register. Its common to start off your fishless cycle with 4ppm, but thats just give it a good start without the need to top up so frequently. The common consensus is that 6ppm + is where you start to kill off the bacteria you are trying to grow.

Good bacteria will grow on anything where there is surface area and oxygenated water flow. Thats typically on filter media in your filter. But it will grow on substrate, glass, decorations. Anything with surface area and good water flow. With regards to substrate, the surface will support denitrifying bacteria that turns ammonia into nitrate. If you have a deep substrate, you might be able to nitrifying bacteria (which thrives in oxygen poor environments) which consume nitrate giving off nitrogen gas. This is difficult though. TLDR. Your substrate will support a significant amount of bacteria, you may be correct with the 90/10 split. Depends how good your filter is i suppose.

 

[Andy Sager]

Welcome back to the fish keeping world. I can help you with some of the old "slang" as I started keeping fish over 50 years ago myself.
To help clear up a couple of things, "Cycling" has always been happening in an aquarium but back then, it was called " conditioning" or "New Tank Syndrome" and you are correct that adding fish slowly and doing routine water changes would usually be enough to not have the fish die off from too much ammonia or nitrite. Doing the fishless cycling is just a way to achieve the same goal without potentially killing fish.
Aiken's explanation of the process is pretty spot on. The goal in the end, even with a fishless cycle, is to not overload the biological system too quickly so continuing slowly is a good thing.
As for where the nitrifying bacteria are most present, that depends on the filtering system you are using. When we used the inside corner filters, the bacteria would be more in the area nearest the filter and inside the floss since that's where the most oxygenated water would be. When we switched to undergravel filters, the bacteria bed was more spread out because the water was flowing through the gravel on a larger scale. When motorized outside filters ( remember the old Bubbleup filters LOL ) became the newest method, more bacteria was in there since that's where the highest amount of oxygen would be found. Bottom line, they go to where the oxygen is.

I can't say for sure where your nitrate level went. Live plants will absorb it if you have any. Anaerobic bacteria will consume it if there are areas in the tank which are low in oxygen which is where these bacteria grow. If you have a deep substrate and not using an undergravel filter, those low oxygen areas will be lower in the bed. Be careful not to disturb these too much when doing maintenance as they can be very helpful in completing the whole nitrification process. Here's a good little article that explains it in more detail: Aquaworld Aquarium - Article - Anaerobic Bacteria in Freshwater Aquariums - The Often Incorrectly Vilified Beneficial Bacteria
How it got there in the first place is something you should check. Many water sources now have nitrates in them so that may have been where is came from. If it is, you need to know this for when you are doing water changes. There are now products that can remove it from the water before you add it into the aquarium. (It's like the old days when we would let the water sit to allow the chlorine to dissipate before using it. ) What you want to see is a nitrate level coming from the nitrification of the ammonia source ( either bottled or from your fish. ) Once you have a 0 ammonia and a 0 nitrate level and some amount of nitrate after having a high level of ammonia and nitrite, your tank is " cycled". At this point it's safe to start slowly adding more fish.

I hope this helps

 

[saiwong]

When we used the inside corner filters, the bacteria would be more in the area nearest the filter and inside the floss since that's where the most oxygenated water would be. When we switched to undergravel filters, the bacteria bed was more spread out because the water was flowing through the gravel on a larger scale. When motorized outside filters ( remember the old Bubbleup filters LOL ) became the newest method, more bacteria was in there since that's where the highest amount of oxygen would be found. Bottom line, they go to where the oxygen is.

Yes, I used corner filter boxes when I previously kept fish. Used to pack them with floss, gravel and carbon. I believe I only started hearing of under-gravel filters near the time I left the fishkeeping hobby. Never heard of the external hang-on the back filters. This is new to me, but probably old news to other members of this forum !

If it is, you need to know this for when you are doing water changes. There are now products that can remove it from the water before you add it into the aquarium. (It's like the old days when we would let the water sit to allow the chlorine to dissipate before using it. ) What you want to see is a nitrate level coming from the nitrification of the ammonia source ( either bottled or from your fish. ) Once you have a 0 ammonia and a 0 nitrate level and some amount of nitrate after having a high level of ammonia and nitrite, your tank is " cycled". At this point it's safe to start slowly adding more fish.

I hope this helps

Yes, this is what I used to do. The day before I do a water change I will fill a bucket full of water and just let it sit for a day to remove the chlorine. No chemical de-chlorinator was used. Now-a-days it seems like you need to be a chemist with all these chemical tests.


My plan, once I've got the aquarium cycled, is to start with 2 or 3 guppies and breed them. This I feel is a kickstarter reminder of what I used to do. Breed baby guppy fish and have them in a separate baby fry tank. I used to enjoy watching them grow each day and when they got large enough (not to be eaten by the adult guppies) I would introduce them into the adult tank.

 

[Andy Sager]

Yes, I used corner filter boxes when I previously kept fish. Used to pack them with floss, gravel and carbon. I believe I only started hearing of under-gravel filters near the time I left the fishkeeping hobby. Never heard of the external hang-on the back filters. This is new to me, but probably old news to other members of this forum !



Yes, this is what I used to do. The day before I do a water change I will fill a bucket full of water and just let it sit for a day to remove the chlorine. No chemical de-chlorinator was used. Now-a-days it seems like you need to be a chemist with all these chemical tests.


My plan, once I've got the aquarium cycled, is to start with 2 or 3 guppies and breed them. This I feel is a kickstarter reminder of what I used to do. Breed baby guppy fish and have them in a separate baby fry tank. I used to enjoy watching them grow each day and when they got large enough (not to be eaten by the adult guppies) I would introduce them into the adult tank.

Yes, now-a days, you almost do need to take a chemistry course LOL. Here's why: Public water as changed, well waters have been contaminated, many municipalities switched to chloramine ( a chlorine/ammonia mix) instead of chlorine so a simple dechlorinator won't cut it if you are dealing with chloramine and just letting water sit does nothing . ( you can check with your local water company to find out what they are adding to the water.) We blindly went about adding fish while the bacteria bed established itself but when more research was done and chemicals became more easily available, in order to KNOW and not GUESS, test kits came into being. In some regards, that was a good thing, in other regard, it became a case of " a little bit of knowledge in the wrong hands can be dangerous". Personally, I like to know and not guess.
You missed a fun era of the undergravel filter. A great idea at the time but in the end, more trouble than they were worth imo. The best invention (imo) for the marine tank was the introduction of the wet/dry filtering system. A whole concept built around the processes the public water systems use to sanitize water. It can be used in freshwater as well but can be costly depending on the set-up and not really necessary for the small unloaded aquariums. I still used sponge filters and corner filters in my last hatchery.

Lastly, fair warning on Guppies, there are a lot of bad genetics out there in Guppies. Be mindful where you get your breeder fish from as many do not breed true anymore.
Welcome back to the hobby

 

[saiwong]

Anyway to update you, I still got nitrite & nitrate levels of zero for the next few days. So decided to start a new aquarium cycle from scratch.

This time I swapped SeaChem Stability for Tetra SafeStart.

The cycle started the same as before, and after a few days I got nitrite & nitrate levels..... but then the same thing happened nitrite & nitrate levels fell to zero and stayed there for the next few days

Was really puzzled so asked the advise of the fish store. They recommended I go back to using SeaChem Stability and also get a bottle of SeaChem Prime as they both work well together

So, hopng I have better luck on my THIRD TRY !

So the 3rd cycle, things happend the same as before, and after a few days I got nitrite & nitrate levels..... but then the same thing happened nitrite & nitrate levels fell to zero and stayed there for the next few days

so what is happening ??? why are the cycles crashing and nitrite & nitrate levels are zeroing after a few days. I am totally puzzled as to what is happening. Can someone help ?

 

[Aiken Drum]

Im not really seeing an issue here.

Dose ammonia to 2ppm. Test daily. If ammonia drops below 1ppm then redose it back to 2ppm. When you can dose 2ppm ammonia and 24 hours later see zero ammonia and nitrite you are cycled. I wouldnt even be testing for nitrate.

 

[saiwong]

Today I retested and got the same results as yesterday



Ammonia 0.5ppm

Nitrites 0 ppm

Nitrates 0 ppm



I was curious as to why I am getting these results so did further tests



PH 6.5



my initial PH was 7 so what was causing it to lower. I read that aquarium cycles do cause PH to lower and also active bacteria might not populate if the PH is low and recommend PH of 7 or above. So does my lower PH a cause of the stalled/slowed cycle ?



I also tested KH. With the NT Labs test your initial water colour should be blue and you keep adding drops until it turns yellow. With my first drop it was yellow !!!



KH 1 dkh



so wondering if this is stalling my cycle.



to raise my PH I've heard you can use baking soda/bicarbonate of soda or do a water change. Which would you recommend (or will either do) ?

 

[saiwong]

additional ...

I have some water de-chlorinated with SeaChem PRIME ready to do a water change, so I tested its KH

added the first drop and the water was yellow !

then I tested my tap water

added the first drop and the water was blue

then added the second drop and the water turned yellow

so

de-chlorinate water (via PRIME) KH 1 dkh

tap water KH 2dkh

so it seems I really need something to raise my KH and suspect this might be causing my problems in the aquarium cycle

recommendations please

 

[Aiken Drum]

Im simply not seeing anything to suggest your cycle is being stalled. What in particular is making you think this?

Your ammonia is 0.5ppm so redose ammonia back to 2ppm. Restest tomorrow. If its below 1ppm redose ammonia back to 2ppm. If its not below 1ppm leave it 24 hours and repeat the tests, and redose as needed. Once you can dose 2ppm ammonia and 24 hours later you see zero ammonia and nitrite you are cycled.

Prime cant possibly affect carbonate hardness.

If you want to raise KH add some crushed coral or cuttlefish bone into your filter. But as said, there is nothing in your testing to suggest your cycle is being stalled.

 

[saiwong]

I was told that for a good aquarium cycle you need PH at 7 or higher.
PH levels are affected by KH
My PH reading today was lower than before at 6.5 so my cycle might be slowing

you say PRIME cannot affect KH but today I did tests on my water
one with PRIME and one without and the
KH reading with PRIME was lower than straight from tap water test
so what caused the difference in measurements ?

de-chlorinate water (via PRIME) KH 1 dkh
tap water KH 2dkh

both readings seem low (since at start of cycle attempts last month I measured KH 4)
so what is causing tap water KH to lower ?

also even after cycle has complete, for good steady aquarium environment with steady PH you want a higher KH level, correct

 

[Aiken Drum]

The only tests you need to be doing while cycling are ammonia + nitrite. Everything else is just complicating things, and causing you confusion when results arent what you expect.

But, since you are going down the water chemistry rabbithole. pH has nothing to do with whether you can cycle or not. Many people keep fish in pH as low as 6 and cycle their tanks just fine. Im not sure where you have got it from that you need pH above 7 or that pH dropping is a sign of your cycle crashing.

It may be a misunderstanding of the word alkalinity. Alkalinity is a measure of some things that are disolved in water. Carbonate hardness (KH) in most situations make up the majority of alkalinity. KH is the amount of disolved carbonates and bicarbonates disolved in the water. KH and alkalinity are often considered to be the same thing. This is different to the common usage of alkaline which typically means a pH above 7. Alkalinity and alkaline mean different things. Increasing alkalinity will raise pH, but you will have alkalinity in acidic water.

KH is important for 2 things. It stabilises pH as it can absorb acid. Also, the nitrogen cycle uses up KH to process ammonia into nitrate. Once KH has gone, your pH will crash and your cycle cant function. KH dropping is a sign that your cycle is working, but a better sign is your ammonia and nitrite tests.

If you are basing your thoughts that your cycle has crashed purely on because your pH is going down, then this is a misunderstanding. If you are dosing ammonia and it is going down your cycle is functioning. If you are dosing ammonia and it doesn't go down it isnt.

You are a little over 2 weeks into what is typically an 8 week process, possibly much longer. Nowhere near enough time to determine if you are having issues. All you really need to be worried about is testing for ammonia and nitrite every 24 hours. If your ammonia drops below 1ppm, redose it back to 2ppm. When you are able to dose 2ppm and in your test 24 hours later see zero ammonia and nitrite you are cycled.

Your KH is low, and this could be why your pH is dropping. But there are other processes that acidify water. If you want to raise the KH then add crushed coral or cuttlefish bone into the filter. This will be a steady source of calcium carbonate which will raise both KH and GH and keep your pH steady. If your tap water has good KH levels then water changes will be sufficient to replenish it.

As to your KH test and prime. Prime is a water conditioner. It cant possibly affect the amount of carbonate/ bicarbonate disolved in the water. Your test is a home test kit, not laboratory testing. All sorts of things can cause your test to give inaccurate results. While it may be that the prime is causing an innacurate test result, it cant in reality be causing more or less KH.

 

[saiwong]

thanks Aiken for your advise. All this 'chemistry' side of things is new to me.
When I previously kept fish 40+ years ago there was no such water testing and
you just did things to a routine that you were taught from person to person.
So I am bombarded with so much information and events that trigger 'alerts' that
cause me to think things might be going wrong. So I will take your advise and focus on
ammonia + nitrite

 

[Aiken Drum]

You can make it as simple or as complex as you like. See whats happening with ammonia and nitrite to start with. Give it at least another week before deciding something is going wrong. You are at the beginning of a long process.

If you are confident your KH test is correct then adding some crushed coral or cuttlefish bone to your filter won't be a bad thing. I would try and get your water report from your water company though. Their tests will be more accurate than your home test kit.

I have to ask. If you have past experience of keeping fish why are you doing a fishless cycle?

 

[saiwong]

> I have to ask. If you have past experience of keeping fish why are you doing a fishless cycle?

I am doing a fishless cycle because other members on several fish forums
recommend it (not to be cruel to the fish).

Previously 40+ years ago I would do a fish-in cycle (as I knew no other method)
and never lost any fish (start with a small number and slowly grow to fill aquarium)

 

[Aiken Drum]

Fish in cycle isnt cruel if done properly. Also better testing makes it much safer to do now than it was back in the day. I really hope my asking the question, and your response makes you think about what you are doing, and why, a little more.

You've never lost fish and other people are saying what you did in the past is cruel?

 

[saiwong]

>You've never lost fish and other people are saying what you did in the past is cruel?

Not specifically directed to me, but just a general opinion from people that

fishless cycle = good and kind, as fish are not hurt
fish-in cycle = bad and cruel to the fish

 

[Aiken Drum]

>You've never lost fish and other people are saying what you did in the past is cruel?

Not specifically directed to me, but just a general opinion from people that

fishless cycle = good and kind, as fish are not hurt
fish-in cycle = bad and cruel to the fish

Personally if i was comfortable doing something and know what to expect, then that's how i would do it.

Really, below is the most relevant paragraph from everything above.

Previously 40+ years ago I would do a fish-in cycle (as I knew no other method)
and never lost any fish (start with a small number and slowly grow to fill aquarium)