Fishless cycle query

[Benallen2000]

Hi, I have kept fish for many years but never tried a fishless cycle. My 6 year old has a small 23l fluval edge. We’ve been using dr tims ammonia and it’s got to the point where ammonia is undetectable, nitrite spiked as expected and then has dropped right down to barely detectable. This happens over night and has done for several days. I checked nitrate with the plan of doing a 50% water change prior to adding any live stock. The nitrate was 100ppm so I did a 50% water change and checked nitrate again that evening. It’s still at 100ppm.

Also my nitrite has reappeared. I sssume this is because the water change may have killed off some bacteria so I’m not too concerned about this, it’s improving slowly as we speak.

However I did another 50% water change and the nitrate is still at 100pm.

Did I just have really high nitrate to begin with or is the test playing up? And should I continue with big water changes to see if it has the expected impact.

Any advice appreciated as thought I was good to go until I had the surprise nitrate reading.

Cheers

 

[seangee]

The water change should not have affected your bacteria if you used a dechlorinator. If you did not it will have set your cycle back a bit - but you won't need to start again from the beginning.
The end result of the nitrogen cycle is nitrate. If your tests only go up to 100 it will stay that way until you get it down to the next reading below 100.
Also test your tap water. The maximum permissible nitrate level in UK tap water is 50ppm. My own water supplier pushes that to the limit, so much that I won't use tap water in my tanks (or to drink). Testing the tap water should at least prove the tests are working.
Since you don't have any livestock why not just change 100% of the water (using dechlorinator). That will take your tank back to what comes out of your tap.

 

[Benallen2000]

Yeah I use dechlorinator. Good idea to check tap water though. I’ll do that now. I guess I’ve put a lot of ammonia in over the last 3 weeks and it gets converted in to nitrate.

If tap water shows low nitrate I’ll do a massive water change tomorrow. Poor lad is desperate for some fish.

Thanks for your time

 

[Benallen2000]

So my tank is now at the same level as my tap water for nitrate (somewhere between 12.5 and 25ppm). If my ammonia and nitrite remain stable overnight (based on previous good stability for almost a week and me just adding a little bit of ammonia to new tank water) I will add a couple of fish.

Cheers

 

[10 Tanks]

Hello Benallen. If you don't have a filter or some substrate from an established tank, you can use API's "Quick Start". It's a liquid bacteria starter that you dose in a new tank set up every time you change half the tank water. I recently set up a 52 gallon tank, filled it and dosed the liquid bacteria according to the instructions. I just put in a dozen or so Guppies and then just changed half the tank water every few days and dosed the bacteria starter when I changed out the water. The tank now has a couple of dozen Guppies and 10 or so Buenos Aires Tetras. All are doing well. The tank has been up and running a couple of months and now gets a 50 percent water change weekly. Pretty easy.

10 Tanks (Now 11)

 

[seangee]

So my tank is now at the same level as my tap water for nitrate (somewhere between 12.5 and 25ppm). If my ammonia and nitrite remain stable overnight (based on previous good stability for almost a week and me just adding a little bit of ammonia to new tank water) I will add a couple of fish.

Cheers

Sounds like a plan. FWIW I always recommend live plants, but with the nitrates in your tap water I would suggest this is important. The logic is that plants (especially fast growing plants) will consume the ammonia without converting it to nitrate so once established the nitrates won't go up. You still need to do weekly water changes but its something to bear in mind.

 

[10 Tanks]

Hello again. Actually, you don't even need the plants. That 50 percent water change every few days, will remove half of the dissolved nitrogen from the fish waste and dilute the other half to a safe level in all the clean, treated tap water. But, you must change half the water every few days, or toxins can build up and make the fish sick.

10 Tanks (Now 11)

 

[TwoTankAmin]

Quick start cannot contain the needed Nitrospira bacteria because there is a patent on them and the method for detecting them. This patent is held jointly by Dr. Tomothy Hovanec and Marineland which is now part of a conglomerate. The conglomerate alos owns Tetra and this division produces their version of starter bacteria which also will contain Nitrospira. It is called Safe Start or Safe Start Plus.

A tank will not be cycled without Nitrospira and when it is whatever bacteria was in other manufacturers products will be gone from the tank.

However, given the level of nitrate in your tap, you are almost fighting a losing battle during a cycle in terms of ointrate levels in a tank. The problem with nitrate is it creates some nitrous acid in he water. Normally weekly water chages contain this and we never see any ffects from persistently elevate nitrate.

However, during a fishless cycle it is possible. Especially if one has nitrate in their tap. So, were you testing the pH along the way or just the nitrogen compounds? My guess would be you did not test for pH. What likely happend was you did get the tank cycled. But yo8u also had way to much nitrate building up and than likely lowered your pH. One the pH ducks under 7.0 by more the a couple of .1s, the cycle starts to slow and will even apopear to stop. It hasn't, but the parameters change and the bacteria cannot process the form of ammonia in water when the pH is acid. This is called ammonium as opposed to ammonia, The bacteria want the latter.

Since you have no fish yet, any mistakes made only mean more time and no fish harmed. But the problem you have is that it is advised that one try to keep the nitrite levels in a tank at 20ppm or lower. One way to do this is with live plants in the tank. They will use ammonium when they can get it, but can use nitrate whey the cannot. However, they do so less efficiently because they have to turn it back into the ammonia forms.

Floating plants and stem plants use nutrients the fastest and are easy to care for if you can add them to your tank. You need to make a plan now for how you will handle the nitrate down the raod when you get fish. It is difficult to lower nitrate when it comes in with yoru tap. But it is not impossible to do so.

Depending on the pH and hardness of your water one simple solution may be to dilute the water a bit with distilled. In the states supermarkets have it for about $1/gal (3.78l). Your tank hold a bit more than 5 U.S. gals. Since you do not fill it to the very top and you add things that will displace some water, I would call it 5 gals. so if you can dilute the 5 to be 3.5 tap and 1.5 distilled, you lower the nitrate by 30% or to 17.5 ppm instead of 25.

If you are changing half of your water every week you would need 2.5 gals total of which .75 would be distilled and 1.75 would be tap.

{I have to get off my PC for a while and will try to calc. all the litres to go with the gals above later.}

 

[10 Tanks]

Hello again. API's Quick Start allows you to add fish immediately to a new tank set up. I've used it when a used filter or substrate wasn't available to instantly cycle a new tank. When starting a new tank, you do all the set up and fill it. I keep larger tanks, so I typically wait a day or two to allow the water to reach room temperature. I dose the liquid bacteria according to the instructions and add a few fish. I'll change half the tank water a couple of times a week for a few weeks and make sure to dose the Quick Start when I change the water. After a few weeks, I gradually add the fish I want and always change at least half the tank water weekly.

10 Tanks (Now 11)

 

[Benallen2000]

Thanks guys. Good stuff to read through and consider. I read about a drop in ph and its effect on the cycle last night too. Ph seems ok in tap water from previous memory but will certainly check again. Thanks for all the help

 

[Ichthys]

What test kits are you using? Very unusual to get a surprise nitrite reading unless you’ve added more ammonia.
What’s the KH of your tapwater? Bacteria use carbonates, so with a very low KH they can use it up which will then cause the pH to drop.

 

[Benallen2000]

Salifert for ammonia and nitrite. Tetra for nitrate.

I did add some more ammonia to keep the cycle going but only a quarter dose of the dose I was using to achieve 2ppm for fishless cycle.

Not sure about kh of tap water I’m afraid.

Repeating all tests this afternoon after yesterdays water change

 

[Ichthys]

Sorry, I meant strips or liquid. Strips are useless and I wouldn’t believe anything they ever told me.

2ppm ammonia becomes 5.4ppm nitrite, which becomes 7.3ppm nitrate.

 

[Benallen2000]

thanks. Liquid. Yeah I’ve always used the liquid kits as had 300litre marine previously so needed accuracy. Used RO water then though

 

[Benallen2000]

Just checked tank parameters. After a huge water change (pretty much 100%) yesterday and only enough ammonia added to take it up to just under 1ppm, the nitrate is back to sky high. Doesn’t add up.

Ammonia undetectable, nitrite spiked slightly (approx 2ppm), nitrate sky high.