2nd hand tank, cycled already?

[QueenBee]

Got a second hand fish tank today, - Blue lanet 160L l, built in filter, lights etc. It had had 2 parrot fish in it - the previous owner emptied it yesterday when she sold the fish. I took it home, filled it with water, put in the same gravel, same bio system, none of it cleaned (so I could kick start the nitrogen cycle).

added appropriate dose of Prime. An hour later, out of curiosity, I tested the water. Ammonia and nitrates zero, nitrates between 20-40.

I was expecting some ammonia perhaps, but not nitrates. Is it possible the bacteria are already well established and it won't need to do a full cycle? (Obviously get the nitrates down.before using it)

I've added fish food to kick start some ammonia any way. Haven't changed the water as it was new already,

wondering if I should keep using Prime daily, and do daily water changes to get nitrates down?

or wait and see if i get an ammonia spike?

have only just turned the heater on, and won't be putting any fish it in yet anyway!

 

[Byron]

The nitrifying bacteria will be present provided the media and/or substrate did not completely dry out. But that is not the real concern here.

Nitrates as high as 20-40 is a problem. Have you tested your tap water on its own for nitrate? If the tap water is zero nitrate, then the substrate and filter media need a very thorough cleaning. With no fish in the tank, nitrate should be close to if not zero. It is all the organic gunk in the substrate and filter media that is the source of nitrates within the system.

The other concern is any pathogens that may have come with the filter media and substrate. The only way to prevent this is to discard all filter media and use new (or your own used).

 

[seangee]

Have you added any ammonia? It will always be zero unless some is introduced.

 

[QueenBee]

Just tested tap water - that's the problem, the nitrates in my tap water are reading 20-40. I had checked my other 2 tanks this morning, had similar nitrates levels, so did water changes.

That was a few hours ago, I used Stress Coat when I added the new water, but testing again mow, the levels haven't changed.

At least I know it's due to the tap water ...

But what do I do now?? Do I add Prime now? Daily? Or multiple doses to get it lower? Water changes clearly aren't going to work

 

[QueenBee]

Have you added any ammonia? It will always be zero unless some is introduced.

That's what I was checking - I assumed ammonia would be zero, but wondered if the tank was already cycled - i.e., zero ammonia because the bacteria are there breaking that, and nitrates down from the bio filter that has been in place for 6 ,months - the tank was only emptied last night

 

[Byron]

Just tested tap water - that's the problem, the nitrates in my tap water are reading 20-40. I had checked my other 2 tanks this morning, had similar nitrates levels, so did water changes.

That was a few hours ago, I used Stress Coat when I added the new water, but testing again mow, the levels haven't changed.

At least I know it's due to the tap water ...

But what do I do now?? Do I add Prime now? Daily? Or multiple doses to get it lower? Water changes clearly aren't going to work

There are ways to deal with nitrates in the source water, and those members who have gone down this road can better advise you. @AbbeysDad is one.

 

[QueenBee]

There are ways to deal with nitrates in the source water, and those members who have gone down this road can better advise you. @AbbeysDad is one.

the tap water hasn't always been like this - I've had low level nitrate readings in the tank a week ago. It explains why I've needed to.do water changes every 3 days this week though. Thought it was my tank.being the problem!

 

[QueenBee]

My local council tests the water 'regularly' -doesn't say when it was last tested, but those readings show nitrate as being 4.7mg/l. Is that high? Would that's be the equivalent of 47 on the test kit?

 

[Byron]

My local council tests the water 'regularly' -doesn't say when it was last tested, but those readings show nitrate as being 4.7mg/l. Is that high? Would that's be the equivalent of 47 on the test kit?

The unit mg/l (milligrams per liter) is equivalent to ppm (parts per million) which we use in the hobby, so 4.7 mg/l is 4.7 ppm, and that is fairly low (round it up to 5 ppm) and would be OK if it does not get much higher. All of my tanks run in the 0 to 5 ppm range. Nitrate at 20 ppm is harmful to fish, with varying results depending upon the species, the level of nitrate, and the exposure time. But nitrate is toxic just as ammonia and nitrite are, it simply works differently.

 

[QueenBee]

Good news - I have a small amount of a ammonia in the tank now, having added sinking wla bunch of sinking wafers to the water the day before. at least I know for sure where it's at in terms of the nitrogen cycle

 

[Byron]

Good news - I have a small amount of a ammonia in the tank now, having added sinking wla bunch of sinking wafers to the water the day before. at least I know for sure where it's at in terms of the nitrogen cycle

If you have fish in this tank, which I understood you do, you should not be adding anything to increase ammonia. Feed them but not overfeed, nothing more. If you are now seeing ammonia above zero, you may have an issue.

I said previously, this tank is most likely cycled.

 

[AbbeysDad]

There are ways to deal with nitrates in the source water, and those members who have gone down this road can better advise you. @AbbeysDad is one.

More and more, especially in agricultural areas, we see high(er) nitrates in source water. I pre-filter most water for water changes using API Nitra-Zorb (A rechargeable resin that removes nitrates). The product comes in pouches intended to be used in filters. Additionally, you need to go an extra mile in keeping tank nitrates low with tank/gravel/filter maintenance. Adding fast growing floating plants that will convert ammonia into plant tissue eventually trimmed and removed will be a huge benefit. Feed lightly and only feed high quality foods, low in grains/grain starch (reduces waste). These measures may allow you to reduce the frequency and/or volume of your periodic water changes. Still, you may need to seek out alternative source water for water changes or use a pre-filter to remove nitrates.

 

[QueenBee]

If you have fish in this tank, which I understood you do, you should not be adding anything to increase ammonia. Feed them but not overfeed, nothing more. If you are now seeing ammonia above zero, you may have an issue.

I said previously, this tank is most likely cycled.

I didn't have fish in the tank, until today. I k st added the fish food to get the cycle going.

Ammonia and nitrite levels went from low back to zero. Day after I did a water change and gravel clean, both were up slightly - ammonia 0.25, nitrites, enough colour in the tube to be above zero, but not quite pale purple / next level up

I added Prime.

This morning, back to zero, and because the nitrates are the same as the tank the fish have been in (about 40), I loved them to the new tank (,4 glass blood fins). I'll be surprised if four fish in a 160L tank trigger a rise in Ammonia. but I guess I'll wait and see.

My plan is to wait a day or two, add 2 more glass blood fins, wait another day or two, and then add the Odessa. Assuming ammonia and nitrite levels remain zero.

Nitrates - still a problem, have contacted local council

 

[Colin_T]

Nitrates - still a problem, have contacted local council

Councils (local governments) don't have anything to do with the water supply. If you have nitrates in the water supply, you need to contact your water company. If they won't do anything, then talk to the local newspapers and get them to run a story on nitrates in tap water and how it is bad for people, animals, birds and fish. If enough people kick up a stink, the water company might do something about the nitrates.

 

[QueenBee]

More and more, especially in agricultural areas, we see high(er) nitrates in source water. I pre-filter most water for water changes using API Nitra-Zorb (A rechargeable resin that removes nitrates). The product comes in pouches intended to be used in filters. Additionally, you need to go an extra mile in keeping tank nitrates low with tank/gravel/filter maintenance. Adding fast growing floating plants that will convert ammonia into plant tissue eventually trimmed and removed will be a huge benefit. Feed lightly and only feed high quality foods, low in grains/grain starch (reduces waste). These measures may allow you to reduce the frequency and/or volume of your periodic water changes. Still, you may need to seek out alternative source water for water changes or use a pre-filter to remove nitrates.

Have you found the pre filter works? Local info I found said adding a filter to your tap water won't fix nitrates, nor will boiling the water.

I got Seachem Maxim, the woman looked it up for me, said it'd more likely to work than the Nitra--zorb BUT, as that hadn't made a big difference, I'll go and get some nitri-zorb as soon as payday comes (broke til then).

I'm testing levels daily; changing the water when the tank level goes higher than the tank water. Tap water is between 40-80 as of yesterday.other fish owners in my area are having problems with high nitrates as well -'I've suggested they test their tap water!!!!