Help with my cycle

[tom731]

Hi, I am completely new to this hobby so sorry if I've made some mistakes!

I recently purchased a 70L (19 gallon) tank and set it up with some live plants in it. On the advice of my local fish shop I then added 6 cardinal tetras after 4 days, after doing my own research I realise that this was a mistake as I was unaware that a fishless cycle was a thing.

Since then everything seems fine and I am beginning to cycle the tank using a mix of my own research and what the fish shop recommended however I am getting confused about the readings. It has been 3 days since I added fish, and a week since getting the tank.

Ammonia was 0.5 ppm yesterday but has gone down to 0.25 ppm today
Nitrite was 0.3 ppm yesterday but has gone up to 0.8 ppm today
Nitrate was between 40-80 ppm both yesterday and today

This seems weird to me as its only been 3 day, surely I shouldn't be seeing any nitrite and nitrate yet? I did a 15% water change yesterday, do these readings mean that I should do one today as well?

Thanks for the help!

 

[Essjay]

It does appear to be fast - did you add a bacterial starter, or mature media?

As long as you do water changes to keep both ammonia and nitrite as near to zero as possible, that's fine. When they stay at zero by themselves you can think of more fish but only a few at a time so you don't overwhelm the bacteria.


Can you check your tap water nitrate, please. 40 to 80 ppm is very high - it should be kept below 20 ppm. But UK legislation allows 50 ppm in drinking water so the level in your tank could be from your tap water.
While you are testing tap water for nitrate, you may as well also test it for ammonia and nitrite. It is always good to know what you put in the tank from the tap as well as what is being made by the occupants of the tank.





Can I just check one thing with you - how hard is your tap water? Shops don't know or don't care that fish should be kept in water with similar hardness to the water they originated. Look on your water company's website for hardness. You need a number and the unit rather than vague words.

 

[tom731]

Thanks for the reply!

I did not use any bacterial starter etc.

I tested the tap water and it seems some of my readings are coming from that:

Ammonia: 0.25 ppm
Nitrite: 0
Nitrate: 20-40 ppm

I also looked at the hardness report which says that they add ammonia to the water and the average nitrate level is 33 ppm. In terms of hardness, for GH they gave the amount of calcium as 78 ppm so I think the dGH is 7.8?

I also measured the dKH of my tap water which is 6 but I was told to use a buffer to bring it to 8 (which it now is in the tank).

My readings still don't explain the amount of nitrite so early on? Also what should I do about the high amount of nitrate as water changes aren't going to get rid of it due to it being present in my tap water.

 

[Essjay]

Did they give that as your hardness or was it the level of calcium in the water quality report? Because they are not the same thing.

UK water companies do use mg/l calcium as a hardness measurement and we have to convert it to the units used in fishkeeping. But I'll wait till I know if that is what they gave your hardness as.

As for nitrate, there are ways of dealing with this. Several members also have high nitrate so I'll leave it to them to explain how they deal with it.

If they add ammonia to your water supply, that converts chlorine to chloramine. When you add dechlorinator it splits the chloramine back into chlorine and ammonia and removes the chlorine part. Some dechlorinators also detoxify ammonia but that effect only lasts around 24 hours. You need to be aware that both detoxified ammonia and un-detoxified ammonia both show up in the ammonia test.
Once the tank is cycled and you have fish, if you use a dechlorinator which detoxifies ammonia, the bacteria will have removed it before it has change to revert.

 

[tom731]

Sorry I misread it, it gave the amount of calcium as 78 mg/l and the dGH as 10.85

 

[Essjay]

Then it is the actual hardness

The two units used in fishkeeping are dH and ppm, fish profiles will give a species' hardness range in one or the other.

As you say, 78 mg/l calcium converts to 10.85 dH (call it 11) and 195 ppm. A bit too hard to be called soft, but a bit too soft to be called hard. Sort of middling.

 

[tom731]

So I measured my parameters again today and I record the following results:

Ammonia: 0.25 ppm
Nitrite: 2.0 ppm
Nitrate: 0.4 ppm

Clearly the nitrite is way too high so I immediately did a 40% water change to bring it down. My tetras are still swimming around fine but are sticking mostly to the top of the tank which they haven't done previously (I don't know if this is them just exploring more or if they are there for oxygen?).

I have bought Seachem Prime which is arriving today so hopefully that will protect my fish.

What I don't understand is why my nitrate is so high when I haven't seen a significant ammonia peak yet, is it possible that I have already moved on to the nitrite stage of the cycle this quickly?

I also did some digging into my nitrate problem and I think the best way would be to use nitrate filter media however I am currently using the filter that came with my tank (Juwel Primo 70), which is the Bioflow one, and this doesn't allow for this (I think). Therefore I think I will need to get a new filter at some point, maybe the fluval U2, although I am not sure how this will effect my tank cycle.

 

[seangee]

Do a 75% water change. If your nitrite is still above 0.25 do another 75% change.
A 40% water change will only reduce your nitrite from 2 to 1.2 assuming your fish don't add anything. This is still too high.
If you are able do this now - its a lot more urgent than tonight or tomorrow.

Nitrate at 0.4 is not a problem. If that's a typo nitrate is not a problem you have to fix today - but nitrite definitely is.

 

[Essjay]

I think the nitrate reading is a typo as it was 40 to 80 yesterday and the tap level is 20 to 40.

Nitrate is the least accurate of our testers. If you are using a liquid tester, one of the bottles will say to shake before using, then to shake the tube after adding it. This is because one of the reagents settles on the bottom and the shaking is to get it back into the liquid. Are you shaking it as per the instructions? Not shaking enough is one of the causes of inaccurate readings.

Your tap nitrate is quite high which is probably where it comes from. Your water company's website should have a water quality report which contains nitrate. It's worth looking on there to see what they reckon your tap level is.


Those Juwel sponges don't actually work. Nitra-sorb might, I haven't needed to use it as I am one of the lucky ones with a tap nitrate below 5 ppm. Other members pre-filter their water to remove nitrate.
@seangee - you have high tap water nitrate don't you? I know you use RO now, but could you help tom371 with the way you dealt with nitrate before please?

 

[seangee]

Other members pre-filter their water to remove nitrate.
@seangee - you have high tap water nitrate don't you? I know you use RO now, but could you help tom371 with the way you dealt with nitrate before please?

I used one of these https://www.pozzani.co.uk/product_info.php?products_id=185

But lets deal with the nitrite first.

 

[Essjay]

I agree. Nitrate is a long term thing, the immediate thing is to keep the fish safe by keeping ammonia and nitrite at zero.

 

[tom731]

I just did another water change, this time around 75% and the nitrites are now reading between 0-0.25ppm.

Thats my bad, I meant 40 ppm for the nitrates not 0.4.

 

[tom731]

Its now been 3 and a half weeks since I started my fish in cycle and I think that it my have nearly completed. Is this normal as this seems quite quick when most guides say 6-8 weeks for a tank to cycle.

I should say that I am doing a fish in cycle but have been using Seachem prime to detoxify ammonia and nitrite as per guides online.

My readings are as follows:

Ammonia: Peaked at 1 ppm on 29th May, it is now 0 ppm
Nitrite: Peaked at 2-5 ppm 2nd June, it is now at 0.25 ppm
Nitrate: Has remained constant at 20 ppm since 25th May (although this could be up to 40 ppm I guess as the colours are kinda hard to distinguish)

Do you think my cycle is nearly done? I know that I have to wait for nitrite to go to 0 completely but does this seem too quick to of happened?

Also I am concerned as my nitrate has not noticeably increased, bearing in mind that my tap water has a high nitrate content (average 33 ppm apparently). I do have some plants in the tank so these could be eating some of it up right?

Thanks!

 

[Essjay]

It will be cycled when nitrite drops to zero.

You said in your first post that you have live plants, and they will have helped. They take up ammonia but don't turn it into nitrite or nitrate. Because you had readings of ammonia and nitrite above zero, it suggests that there are not quite enough plants, or plants that are not fast growers so they didn't take up all the ammonia. Your tank will have grown bacteria to deal with the ammonia the plants didn't remove, but it is possible that as your plants settle in, they'll take up more ammonia making the cycle faster. Plants will only use nitrite as a last resort if there's no ammonia available, so you will need to wait for the nitrite eating bacteria to remove the last bit of nitrite.

Just hang on in there, it will happen