Fish In Cycle Assistance

lilacamy931

Candiru
MFK Member
Jun 1, 2009
255
53
46
Burnemouth
Hi All

So I know this may be cause some controversial opinion but I am going on with a fish in cycle. I've cycled tanks before both fish-in and fishless but can't make heads or tails what is happening with my current tank.

Any recommendations would be great - here are the stats

Tank: 200 litre
Substrate: Sand
Filter: Fluval 306 external canister
Decoration: Mopani wood and live plants
Heater: 26C
Lighting: Aquasky LED

Stocking:
1 x Bolivian Ram
6 x Gold Tetra
16 Neon Tetra

Tank set up on 14th November

Daily water changes usually 30-50% depending on readings from Master Test Kit
Products used: Tetra Safestart
Prime dechlorinator using
Occasionally dosing plant food 1-2 times per week
Feeding - once per day

What has me confused is, we appeared to be going through the transition of ammonia peak and then those levels lowered and the ntitrites and nitrates increased (my thoughts going right direction).

For the last week, it seems to have reverted to just some ammonia readings out of the norm and nitrites/nitrates reading normal. Usually the ammonia is just up to 0.25ppm, tonight we have had 2.0ppm

Fish are swimming fine, not showing signs of distress with actions or colouration and eating healthily.

My main plan is water changes, close watchful eye on the parameters, light feeding and if need be will get another bottle of tetra safestart.
 

tlindsey

Silver Tier VIP
MFK Member
Aug 6, 2011
17,480
15,818
1,645
Ohio
Hi All

So I know this may be cause some controversial opinion but I am going on with a fish in cycle. I've cycled tanks before both fish-in and fishless but can't make heads or tails what is happening with my current tank.

Any recommendations would be great - here are the stats

Tank: 200 litre
Substrate: Sand
Filter: Fluval 306 external canister
Decoration: Mopani wood and live plants
Heater: 26C
Lighting: Aquasky LED

Stocking:
1 x Bolivian Ram
6 x Gold Tetra
16 Neon Tetra

Tank set up on 14th November

Daily water changes usually 30-50% depending on readings from Master Test Kit
Products used: Tetra Safestart
Prime dechlorinator using
Occasionally dosing plant food 1-2 times per week
Feeding - once per day

What has me confused is, we appeared to be going through the transition of ammonia peak and then those levels lowered and the ntitrites and nitrates increased (my thoughts going right direction).

For the last week, it seems to have reverted to just some ammonia readings out of the norm and nitrites/nitrates reading normal. Usually the ammonia is just up to 0.25ppm, tonight we have had 2.0ppm

Fish are swimming fine, not showing signs of distress with actions or colouration and eating healthily.

My main plan is water changes, close watchful eye on the parameters, light feeding and if need be will get another bottle of tetra safestart.


Sounds like parameters are starting to stabilize. I personally wouldn't do 50% a day wc's.
 

FreshyFresh

Polypterus
MFK Member
Aug 24, 2015
673
478
87
50
Buffalo NY
Most of'em are small bio load fish, but that's a pretty large stocking level for a tank you're trying to cycle fish-in for a ~55g tank. I think you're doing the right thing by daily WCs, but they may not need to be quite 50% daily WCs. I would think after 6 weeks or so, you should see nothing but nitrates.
 

lilacamy931

Candiru
MFK Member
Jun 1, 2009
255
53
46
Burnemouth
FreshyFresh FreshyFresh tlindsey tlindsey - thanks for the replies :) Yes I was a fool and just had to add some extra tetras.....that was a definite mistake on my part.

I shall prob go with 30% each day dependent on parameters
 

Drstrangelove

Potamotrygon
MFK Member
Oct 21, 2012
2,694
1,220
164
San Francisco
Any recommendations would be great - here are the stats

Tank: 200 litre
Substrate: Sand
Filter: Fluval 306 external canister
Decoration: Mopani wood and live plants
Heater: 26C
Lighting: Aquasky LED

Stocking:
1 x Bolivian Ram
6 x Gold Tetra
16 Neon Tetra
You started on 11/14.

You have around 4 grams of fish in a 55 gallon tank. (If I am generous and most of the fish are full grown, it's more like 36 grams of fish.)

So, using the higher number, you are adding 0.5 ppm of nitrate a day, but you are also doing huge water changes which is removing food for the BB. So, I'm skeptical that you have any measurable nitrate because there's been practically no ammonia in the tank.

Using the smaller number, you are adding 0.06 ppm of nitrates a day, which is practically speaking, undetectable using common test kits.

Instead of the fishless cycle target of 3.00 ppm ammonia, you are around 0.14 ppm, or under 5% of the target. (That's the higher size for the fish. Using the smaller size, it's 0.02 ppm, or less than 1%.)

And all this ignores the plants which are competing with the BB for ammonia and or nitrates.

I think you have to add ammonia to the tank directly---- unless this is your actual stocking for the tank. In other words, if these are the only fish that will be in the tank, then you're good, but otherwise, you are well short. I wouldn't suggest dumping a lot more food in the tank as that will cause a bacterial bloom and those bacteria will compete with the BB.

The issue is that even if you do this for another 3 months, then put just three 8" fish in that tank, the BB will be only 8% of what you need, and you will have a large mini cycle.
 
Last edited:
  • Like
Reactions: tlindsey

skjl47

Potamotrygon
MFK Member
May 16, 2011
4,284
3,422
164
Tennessee
Daily water changes usually 30-50% depending on readings from Master Test Kit
Usually the ammonia is just up to 0.25ppm, tonight we have had 2.0ppm
ignores the plants which are competing with the BB for ammonia
wouldn't suggest dumping a lot more food in the tank as that will cause a bacterial bloom and those bacteria will compete with the BB.
if you do this for another 3 months, then put just three 8" fish in that tank, the BB will be only 8% of what you need, and you will have a large mini cycle.
Hello; Some weeks, perhaps months, ago A forum member wrote some comments. Wish I could recall who. After some thought it makes sense.

I will attempt to recap. For fish in cycling it goes like this. We put fish in a new tank so they will produce ammonia with the plan being this ammonia will feed the ammonia consuming beneficial bacteria (bb).
Then because we know the ammonia harms fish we dilute it with large water changes (WC). In your case 50% WC each day.
Issue becomes the daily WC are diluting the ammonia to the point that the bb do not have enough of the nutrient, ammonia, to make a proper sized population. This in turn slows the development of the bb type that converts nitrites into nitrates. Sort of a feedback loop that stalls the whole process.

A way around this dilemma could be to simply sacrifice (by this I mean allow them to be poisioned by their own ammonia) a number of fish for a week or few by not doing any WC. That way all the ammonia they produce will be available to get the bb population going.

If I followed the steps correctly the OP had a sort of balance going with the WC's and adding bottled bacteria for a while. I guess then some number of new fish were added "
just had to add some extra tetras..
My guess this upset the tank all at once.
 

lilacamy931

Candiru
MFK Member
Jun 1, 2009
255
53
46
Burnemouth
Drstrangelove Drstrangelove and S skjl47 - thank you both for the replies much appreciated. Both explanation make a certain amount of sense.

About a week ago nitrites and nitrates were reading measurable and it seems I have water changed that beneficial change out.

So could I ask opinion of which option you would go for out of these:-

1. Take the fish to a store (give them away) and go with a fishless cycle

Or

2. Continue fish in cycle. Hold fire on water changes all together and monitor and keep record of the daily parameters to allow the ammonia to build.
Maybe get more tetra safestart alongside this to add more BB to the system as only clicking now I've probably WC'd it out.
Feed the fish once per day to allow ammonia to continue but not have a bacteria bloom.

If go with this route potentially poisoning the fish and could create losses - do I keep the current stock level or reduce?

3. Continue as 2 but add ammonia.

I am very conscious in 4-5 weeks I will be getting some pufferfish to add to this bioload. They are currently babies at 1inch each and fairly expensive fish (which the tank is being built around them). So whatever decision is best for these in the long run is what I would like to do.

Really do appreciate the replies and any further help to correct my mistakes would be great.
 

tarheel96

Polypterus
MFK Member
Feb 2, 2015
457
310
87
North Carolina
What are ammonia and pH now?

You mentioned having other fish tanks. So you don't have any tanks currently running? All this could be avoided by seeding this new filter with some established media.

You need to taper off on the water changes and/or volume so that you're maintaining ammonia at a maximum safe level dictated by pH. At pH 7.3 total ammonia of 2.0 ppm is still only 0.2 ppm of toxic NH3 which is safe. But at pH 7.9 total ammonia of only 0.5 ppm gives you the 0.2 ppm of toxic NH3. At pH 8 and above, total ammonia of 0.25 ppm should not be exceeded.

Nitrite toxicity can be avoided by adding one tablespoon salt (sodium chloride) per 10 gallons of water. Prime/Safe can also temporarily detoxify nitrite (and ammonia) but it must be added daily.

Direct answers to your questions will follow but you need to know your tank pH.

In short, reduce the frequency and volume of water changes as permitted by pH. Hopefully you can keep ammonia at 2 ppm.
 

skjl47

Potamotrygon
MFK Member
May 16, 2011
4,284
3,422
164
Tennessee
1. Take the fish to a store (give them away) and go with a fishless cycle
Hello; This is the more humane choice with the understanding these fish have already been exposed to fairly high levels of ammonia if I read your previous posts correctly. They may be already damaged a bit and may have shorter lives regardless.
It becomes a question of how cruel you are willing to be. It is one thing to make a mistake and expose fish to ammonia and another to actively do such a thing.

in 4-5 weeks I will be getting some pufferfish to add to this bioload
Hello; By adding bottled ammonia to a tank and considering there may be a small population of the bb already, you should be able to get to enough bb population. Keep in mind the balance between bioload and bb is an ongoing and dynamic thing.

It is my take that once a decent population of bb become established, that that population can respond to changing ammonia and nitrite levels fairly quickly. An issue shows up when one side of the balance is changed a lot.
Example is adding a lot of small fish or one big fish to a tank in balance. The amount of ammonia in the water jumps up immediately but the bb can take a day or few to reproduce to get back in balance. ( called a mini-cycle by some). Does not take as long as getting the tank cycled in the first place. This mini-cycle time is when big and often WC can be a good tool.

In your case I might add the bottled ammonia at a dose estimated to be more than the bio-load of the coming puffers. That way when you stop adding the bottled ammonia a day or so before putting the puffers in there should be a lot more bb than needed.
To me it is better to have more bb than needed to handle the new fish load. The bb will die back to a balance in time, but this seems better as there is little chance of an ammonia spike.

Good luck
 
  • Like
Reactions: Drstrangelove
zoomed.com
hikariusa.com
aqaimports.com
Store