Nitrates Not Rising Particularly, Is This Ok?

[Glitzy]

Hi all. I inherited a 150 litre tank which had a single harlequin rasbora and a plec in it. Water fully mature and cycled, but obviously not many fish!

I started off two weeks ago by adding six green tiger barbs. Two days later I experienced a very slight rise in ammonia, nitrite and nitrate. The levels were showing between 0 and 0.5 on the ammonia, 0 and 0.25 on the nitrite and 0 and 5.0 for nitrate. They were kind of half way between the different colours if you understand me (have liquid testing kits).

So I did a 25% water change and levels went back to 0 on all three. Once the levels had stayed at 0 for a week I added another 6 harlequin rasboras. Everything is still sitting at zero a week later. I'd have expected the nitrates to rise to be honest but they just haven't.

I was hoping to add a few more small tetras this weekend, but is everything ok? Have completely lost my confidence with this after so long out of the hobby...

 

[JenJ]

Is this the API test kit? The nitrate test can be sensitive - give the bottles a *really* good shake before you use them. It may be you do have nitrates but the test is not working correctly. Either way, be very happy with 0 for ammonia and nitrite.

It is also possible to have a genuine almost zero nitrate reading, depending on stock, plants in the tank, and the ppm in your tap water.

 

[Glitzy]

Will try shaking. Yes they're API tests.
I think they do work as they showed the initial rise but will try shaking thanks.
Tank doesn't have p,ants as not had a lot of luck with them tbh but has boxwood and rocks for hiding places.

Sorry plants and bogwood. Autocorrect fail!

 

[CezzaXV]

The test solution tends to solidify on bottle 2 on the nitrate test, so it may have done that in the time between your first test and now. JenJ is right, give it a really, really good shake and whacking on the desk (I do this every time I do a nitrate test) and see what it says.

 

[eaglesaquarium]

The problem is that bottle 2 actually has two reagents - one is a solution, the other is an insoluble powder. The powder can settle on the bottom and needs to be thoroughly mixed - much more shaking to get it properly suspended in the solution than one would normally expect. I kind of wish the bottle were clear so that you could see the powder, or at least clear on the bottom.

 

[Glitzy]

Thank you all so much. I gave bottle 2 a really good shake, now reading 20. I'm due to do a water change tomorrow anyway and as the ammonia and nitrite are still 0 I'm happy.

 

[Glitzy]

Okay. I did my 25% water change and thought the gravel could do with a vacum too. Oh my word the water came out BLACK. Problem is the nitrate has now doubled to 40 even though the ammonia and nitrite is still reading 0.

I don't think the gravel has been vacuumed before and I'm thinking I've stirred up trouble...
Will do another water change tomorrow and keep an eye on the levels... Should I in future continue with the vacuuming or leave well alone? Not touched the gravel near the large rocks and bogwood in there,was going to do that with next week's water change but don't want to poison everything!

 

[eaglesaquarium]

Nitrate will always go up in a cycled tank while the ammonia and nitrite stay at zero. That's how it supposed to work. Ammonia is converted to nitrite then to nitrate by nitrifying bacteria. The nitrates can be used by plants, but mostly the aquarist (you) has to deal with the nitrate (water changes) to keep the nitrates down.

I recommend 25% a week, then a 50% change once a month and 75% every 6 months to stay on top of the nitrates. I use a slightly different schedule for myself to use the fish water as a type of fertilizer for my flowers in the garden. I emulate a "rainy and dry" season annually. My fish seem to be thriving with this schedule.

I do the larger changes occasionally to try to keep the tank as fresh as possible. Imagine living in a house where the windows were always closed... fresh air helps us, and so does fresh water for the fish. They are primarily river dwellers which means their water is constantly changing.

Gravel vac should happen as a part of EVERY water change. Dark water is normal. If it hasn't happened in a while don't worry. Just do a section at a time until you get the whole thing done. During the larger changes semi-annually, you want to move the rocks and vac under there too. The fish will be fine with a little disruption. Larger animals move through their habitat normally in nature and move things from time to time. My fish usually check and "supervise" my work. ;-)

 

[Glitzy]

Ok thanks. Wasn't an issue before as I kept my gravel clean and never had this situation! So as the nitrate doubled after stirring up the gravel another wat change would be a good idea?

I mean yes I had increasing nitrates, but not doubling overnight if you get me.

 

[eaglesaquarium]

Did you test the nitrate before you did the water change, or after? You probably didn't stir up NITRATE, just gunk. The nitrate was probably already there before. Nitrate will always build up from keeping fish. ;-)

 

[Glitzy]

Yes, it was reading 20 last night, 40 after gravel vac (left it 2 hours after water change to test)

 

[eaglesaquarium]

40 ppm isn't really high. You could do another to get more gunk, but it isn't required. How high are the nitrates in your tap?

 

[Glitzy]

They're 5

 

[eaglesaquarium]

Nice. Thats a nice low number... You'll be able to keep the nitrates low easily with that. ;-)

 

[Glitzy]

Hmm. Bizarre. Back to 20 tonight. Being as 40 isn't 'bad' will persevere as have been doing without worrying.