Question about fish in cycle

[Carl Engman]

Hi,

My daughter and I recently set up the old 10g aquarium that has been in my parents' attic since my youth. We started everything up based on advice from our local specialty aquarium store. We are using distilled water supplemented with 2 Tbsp of API freshwater aquarium salts and (so far) about a tsp of neutral buffer. We have had 3 juvenile bleeding heart tetras in the tank for 17 days. We added a dose of API Quickstart and the whole bag of tank water from the fish store when we added the fish. We have been feeding a small amount of micro pellet food once or twice per day.

I have been measuring ammonia with API's ammonia test kit and other parameters with the 6 in 1 test strips every couple days since we added fish. At its peak, we had somewhere between 0.5 and 1.0 ppm ammonia. That was at around one week after adding the fish. We are currently sitting at close to, but not quite 0 ammonia. There was the barest detectable tinge of green in the ammonia when I last tested. Our pH is pretty steady at 6.8 or just below.

The fish are happy. I've seen no sign of stress and they eat voraciously at every feeding taking all the pellets we feed within 30 seconds or so.

I'm puzzled though because I still haven't been able to detect any nitrite or nitrate in the water. There is clearly ammonia entering the system. We had a small spike in the week after we added fish and began feeding. And the ammonia is being converted into something since the level hasn't continued to rise... I would have expected to see some nitrite or nitrate by now, but we haven't seen it yet.

Our fish store recommended adding one or two more fish every couple weeks until we reach our desired stocking level, but I'd like to know we have a good population of bacteria working before we make another addition to the tank. I assumed that presence of some nitrate would be the indicator for that. Do we just wait a little longer?

Edit: Just a little more information. Tested the water again tonight. I have zero ammonia now and if there's any nitrite or nitrate it's certainly not obvious to me on the test strip.

Hardness is around 50 dgh.

Also, to head off one possible question; we're using distilled water because our tap water tested at 2ppm ammonia. I figured with a 10g it wouldn't be that much of an extra expenditure and it'd be one less thing to worry about.

 

[Colin_T]

Hi and welcome to the forum

If you have 2ppm of ammonia in your tap water, you should contact your water supply company and get them to fix it.

The only ammonia that should be in tap water should be bound to chlorine to produce chloramine, and the level of ammonia should be less than 2ppm.

You can prefilter the tap water to remove ammonia. Fill up a large plastic container that hasn't been used for chemicals, add a dechlorinator and aerate the water. Add a filter that contains Ammogon or Zeolite and let it run for a couple of days. The Ammogon/ Zeolite absorb ammonia from water and should be able to remove all of the ammonia from the water in the container. You can then use this filtered water in the aquarium. The Ammogon/ Zeolite can be recharged and re-used.

You can grow floating plants in the container of tap water and the plants will use the ammonia.

You can also use a normal aquarium filter that has cycled and the beneficial filter bacteria will use the ammonia and convert it into nitrite and then nitrate. However, removing the ammonia instead of converting it is the better option.

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Most filters take about 4-5 weeks to develop the beneficial filter bacteria. It takes around 2-3 weeks for the first colonies to appear and convert the ammonia into nitrite, and a couple more weeks to convert nitrite into nitrate.

Don't bother testing for nitrates until the filter has cycled because nitrate test kits read nitrite as nitrate. So if there is any nitrite in the water, the nitrate test kit will pick it up and give you a false reading.

If you have live plants in the aquarium, they will use some of the ammonia.

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When doing a fish in cycle, only feed the fish a couple of times a week and do a big (75%) water change 4-8 hours after feeding. Gravel clean the substrate whenever you do a water change.

The fish won't starve and the less food going into the tank, the lower the ammonia levels will be, and the fish will be healthier with less ammonia.

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Don't add any new fish until the filter has cycled. If you add more fish each week (like the pet shop suggested) you will add more ammonia due to the extra fish. And the new fish could potentially die due to going into an aquarium where there is an ammonia reading, albeit a low level.

Basically any ammonia is a problem to fish so the fewer fish that are exposed to it, the better.

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What does the API freshwater aquarium salts contain?
If it is sodium chloride (salt) then that is not the best for tetras or other soft water fishes. These fish come from water without many minerals in and have small kidneys. If they are exposed to salt (sodium chloride) for any length of time, kidney damage can occur.

Salt can be used to treat fish for some diseases, but there are maximum exposure levels and times that must not be exceeded due to the possible risk of kidney damage.

If the aquarium salt has calcium and magnesium in, and does not contain sodium chloride, then it is fine at low levels and won't harm the fish.

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Once the tank has cycled, you should visit the local pet shop and make a list of fish that you like. Post that list on here and we can go through it and suggest which fish go well with each other and in your water.

 

[Jeremy180]

One of three things I see as possible here from those results
#1 If you have a lot of live plants, then after settling in and starting to grow, they may have absorbed the ammonia from only three tetras, provided they are small.

#2 Possibly a faulty nitrite test reagent. Uncommon, but it happens.

#3 Is it possible a test was misread? I myself don't have maximum confidence in interpreting API's results unless I compare it to the card while looking straight down into the top of the tube, and then only in outdoor sunlight.

Even then I am not 100% sure whether I have 8.2 or 8.4PH, lol

 

[Carl Engman]

Thanks for the input.

A couple clarifications: 1)The fish store said to add one or two fish every two weeks (not once a week) but they said not to add any fish until our cycle had completed. We bring them a sample of water for them to test each time we come in to look around to get their opinion on our progress. They say we're not ready yet and I agree.

2) I misremembered the ammonia level in our tap water. Just tested again and it's between 0.5 and 1.0 ppm. My understanding is that level would not be all that unusual for chloramine-treated water which we have in our city.

Some additional questions:

1) After our initial cycle is complete, am i correct in thinking that using our tap water with our 1-ish ppm ammonia, treated with Prime, for water changes will not really be much of an issue? In other words, our cycled filter should be able to process it to nitrate quickly enough?

If so, i don't really see any need for any special equipment to prepare or filter our water for water changes. I'd prefer to just use bottled distilled water until our cycle is complete. But that leads me to:

3) If i use distilled water for my first couple water changes I must use some kind of supplemental salt, correct? Straight distilled water would not be good for the fish. The salts i have are evaporated sea water, so mostly sodium chloride with some other trace minerals. The amount I'm using is very small.

Thanks again! It's a big help!

 

[Carl Engman]

One of three things I see as possible here from those results
#1 If you have a lot of live plants, then after settling in and starting to grow, they may have absorbed the ammonia from only three tetras, provided they are small.

#2 Possibly a faulty nitrite test reagent. Uncommon, but it happens.

#3 Is it possible a test was misread? I myself don't have maximum confidence in interpreting API's results unless I compare it to the card while looking straight down into the top of the tube, and then only in outdoor sunlight.

Even then I am not 100% sure whether I have 8.2 or 8.4PH, lol

Thanks for the reply. I have no live plants. I'm using 6-in-1 test strips and color change on the pad nitrite is pretty subtle at the low end of the scale.

Nitrate looks like it should be a pretty obvious pink when i get to around 20 ppm.

I'm thinking that what's going on is that I'm getting conversion from nitrite to nitrate (else there would certainly be detectable nitrite in my tank at this point) but I just don't have enough nitrate yet to be easily detectable on the test strip. I'll give it a bit longer and keep checking.

 

[Colin_T]

If the ammonia level in the tap water is low (less than 1ppm) then a cycled aquarium with an established biological filter should be able to remove the ammonia fairly quickly (within an hour or so).

If you use a water conditioner/ dechlorinator that binds to ammonia and makes it inert for 24 hours, then the filter bacteria should be able to remove it before it harms the fish.

The main problem with using tap water that contains ammonia from chloramine is you get nitrates faster because the filter has to deal with the ammonia that gets added with the tap water. So you might find you have 10ppm nitrate the day after you do a water change.

The only other issue with ammonia in tap water has to do with the pH of the tap water. If the pH is above 7.0 then any ammonia will be very toxic and if you don't use a conditioner to bind with the ammonia, you could poison the fish. The higher the pH, the more toxic the ammonia becomes. If the pH of your tap water is above 7.6, I would probably prefilter the water to get rid of the ammonia, but the choice is yours and Prime or something similar should make the water safe while the filter bacteria get rid of any ammonia.

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Distilled water has no minerals in and has a GH and KH of 0, and a pH of 7.0.

Because there is no carbonate hardness (KH) in the water, the pH can drop rapidly if too much fish food or waste is in the tank. Fish food and fish waste produce nitric acid, which is neutralised by carbonates and bicarbonates in the water. The carbonates and bicarbonates make up the KH, so without any KH the pH might drop pretty rapidly. However, 3 small tetras are unlikely to cause a major pH drop.

Most tetras naturally occur in soft water that has a GH below 100ppm so pure water is not a big deal for them. Having said that, you want some minerals in the water to stabilise the pH.

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If you want to add mineral salts, you can buy Rift Lake water conditioner from pet shops and online. These are mainly calcium and magnesium based and designed for African Rift lake cichlids that naturally occur in very hard water with a GH above 350ppm.

You would use the Rift Lake condition at about 1/4 strength in a tetra tank and that would increase the GH of distilled water to about 100ppm. It would also push the pH up a bit too, probably to around 7.4-7.6, which won't be a big issue for captive bred fish.

Sea salt is mainly sodium chloride but also contains calcium, magnesium and various other salts (chlorides) and minerals. Unfortunately sodium chloride is bad for fish (and people) when in high doses, and is more harmful to fishes that come from soft water and less harmful to fish that occur in brackish (partly salty) water.

Because tetras don't normally get exposed to salt, they have developed small kidneys that struggle to deal with salt and it can harm or kill them if they are exposed to it for long periods of time (more than 1 month).

 

[Jeremy180]

Thanks for the reply. I have no live plants. I'm using 6-in-1 test strips and color change on the pad nitrite is pretty subtle at the low end of the scale.

Nitrate looks like it should be a pretty obvious pink when i get to around 20 ppm.

I'm thinking that what's going on is that I'm getting conversion from nitrite to nitrate (else there would certainly be detectable nitrite in my tank at this point) but I just don't have enough nitrate yet to be easily detectable on the test strip. I'll give it a bit longer and keep checking.

That explains it, not only can test strips be more easily rendered inaccurate than the liquid ones due to various environmental factors, but 6 in one indicates to me that you are using the tetra brand test strips.
From What I have seen, quality control in general for the tetra brand tends to be lower than others, in my opinion.


I would suspect a bad batch or a contaminated strip long before assuming the nitrite spike was skipped, The Nitrite converting good bacteria almost always take longer to get established than the ammonia eating ones, and cannot even start growing until there is nitrite for them to eat.

EDIT: Just found a lot of complaints about incorrect test results on the customer reviews for the 6 in one tetra test results amazon page.
https://www.amazon.com/Tetra-EasySt...r&reviewerType=all_reviews#reviews-filter-bar

 

[Carl Engman]

I don't think we necessarily skipped the nitrite spike. More like I missed detecting it. We weren't testing everyday.

Some of this is confirmed by tests done at the fish store as well. At 15 days post fish we took a sample to the store. They measured less than 0.25 ppm ammonia, "a barely detectable, but possibly positive nitrite level" (I'm paraphrasing, but the young man helping us at the store went to a couple other employees to get their opinions on our nitrite reading and there was no real consensus), and not enough nitrate to register on the strip. They thought we were most of the way towards having a complete cycle and just recommended waiting for the first clearly positive nitrate reading before we add more stock to our tank.

It's possible that we and the fish store are both using test strips from one bad lot, but I don't think it's very likely. They do this testing routinely for all their customers buying new fish and I presume they are using the same test strips for monitoring their own water. I'd think they would probably catch it if they started getting anomalous readings.

One other thing occurs to me; we did add a piece of driftwood at around 8 days. Is it possible that there's enough algae contributed by the driftwood to have an effect on ammonia, nitrite, or nitrate levels? I don't see any obvious algae growth, but thought that might be a possible confounding factor?

Anyway, I'll continue to wait patiently and I'll be vigilant for signs of stress. Like I said above, the fish seem to be very happy. They are eating, swimming, and socializing well.

 

[Jeremy180]

I am seeing almost all of the negative reviews of this product being expiring before the use by date, huge numbers of reviews stating that they are fairly good (usually qualifying it as "good for the money") when they work, but also have frequent reports of a lot of bad batches, especially recently.

 

[Carl Engman]

Noted. We purchased a new bottle of strips a couple days before we set up our tank that are well within the use-by date. They have been handled and stored carefully. Not saying that nothing could be wrong with them, but it would have to be a factory problem and not an expiration problem or improper handling/storage problem.

Regardless, I think we've only got around 5 strips left of the first bottle. I was already planning to get the API liquid test kit when the strips run out since it seems to be more cost effective and it is also more sensitive. My 8-year-old daughter likes doing the ammonia test with me. She's a budding scientist. It'll be fun running a whole rack of tubes.

 

[Jeremy180]

Agree with Colin on the ammonia lock recommendation, by the way.
Just don't let it lull you into a false sense of security. True, it converts unionized ammonia into ionized ammonia, but this is only temporary, wearing off in day or two.

It is still harmful, and better defined as "less toxic" than "safe".

As to nitrite being neutralized by ammo lock, I somewhat doubt anything more advanced than either sodium chloride (salt) or magnesium chloride (a bit safer for salt sensitive species, but also less effective at blocking nitrite blood uptake) is the active ingredient for this purpose.

The main way nitrite harms fish is by bonding with red blood cells and reducing the blood's ability to carry oxygen.
This is functionally Identical to carbon monoxide poisoning in humans, with the difference that chloride, whether as magnesium chloride or regular salt, can be used to partially block the nitrite from bonding with the red blood cells.

 

[Jeremy180]

Noted. We purchased a new bottle of strips a couple days before we set up our tank that are well within the use-by date. They have been handled and stored carefully. Not saying that nothing could be wrong with them, but it would have to be a factory problem and not an expiration problem or improper handling/storage problem.

Regardless, I think we've only got around 5 strips left of the first bottle. I was already planning to get the API liquid test kit when the strips run out since it seems to be more cost effective and it is also more sensitive. My 8-year-old daughter likes doing the ammonia test with me. She's a budding scientist. It'll be fun running a whole rack of tubes.

API's tests are a good balance between price and quality, in my experience.

 

[Carl Engman]

Agree with Colin on the ammonia lock recommendation, by the way.
Just don't let it lull you into a false sense of security. True, it converts unionized ammonia into ionized ammonia, but this is only temporary, wearing off in day or two.

My understanding is that I need to worry even less about ammonia due to the low pH of my water. My current tank water and my tap water + Prime both read at around 6.8. Even at 1 ppm TAN that gives me a NH3 concentration of 0.0036 ppm which gives me around an order of magnitude safety factor. I realize if I want to rely on this, I need to be sure that I'm not getting any rapid swings in pH, but it would have to swing pretty close to 8.0 before the NH3 reaches toxic levels. I also plan to test for ammonia and nitrite the day after all water changes to make sure that added ammonia is getting cleared.

 

[Colin_T]

ammonia changes from reasonably non toxic at a pH below 7.0, to toxic when the pH hits 7.1.

each point above 7.0 amplifies the toxicity, and at a pH of 8.0 any ammonia (even 1ppm) will kill all the fish in the tank in a very short time.

If you can keep the pH around 6.8 while the filter is cycling then the fish will do better than if the pH goes above 7.0.

 

[Carl Engman]

ammonia changes from reasonably non toxic at a pH below 7.0, to toxic when the pH hits 7.1.

each point above 7.0 amplifies the toxicity, and at a pH of 8.0 any ammonia (even 1ppm) will kill all the fish in the tank in a very short time.

If you can keep the pH around 6.8 while the filter is cycling then the fish will do better than if the pH goes above 7.0.

I appreciate your generosity with the information you've provided. I don't really want to quibble here, but I understand this bit of chemistry and your explanation above is oversimplified (which I can understand considering we're conversing on a web forum. It's probably appropriate to oversimplify in most cases.) The truth being that the NH3 concentration (given 1ppm TAN and temp of 76F) follows a curve like this with respect to pH:

The basis for my post above is that at 76F and pH 8.0 with TAN of 1 ppm, the concentration of NH3 should be about 0.05 which according to several references I've seen is detrimental in the long run, but tolerable in the short term.

Since I'm currently at pH 6.8 and zero ppm TAN, I'm in a pretty safe zone. I would have to add a considerable amount of ammonia and my pH would have to increase a good bit before I hit any kind of danger zone. If I were to do a 50% water change now with Prime-treated water from my tap I would expect to end up with 0.5 ppm ammonia and pH of 6.8 immediately, and I expect it would be cleared pretty quickly. I'm no longer concerned with the ammonia in my tap water.

Nitrite would be my concern at this point since I'm not yet absolutely convinced that I have a good colony of nitrobacter. I think the signs point to there being some active nitrobacter, but I won't be convinced until I see some nitrate.