Help in confused

[D Robinson]

Hi all, I have a 30L beta tank which has been set up for nearly a year, some fake some live plants (floating) for the last few month ps I have been having massive nitrate and nitrite problems (off the charts high) but the Betta and shrimp seem absolutely fine. I have a 150L that’s really stable and had smaller tanks before, the same thing happened a while ago so I stripped the tank and replaced everything and now it’s happening again? Any advice would be great!! Sorry the pictures aren’t great

[FrozenFins]

What are your nitrites at? Is there any amonia in your tap water? Was your tank cycled?

a good number for nitrates is 10-20ppm. If you have higher then that, it could be your fertilzer that your dosing. If your using a nitrogen base fertilizer (like easy green) this is probably your problem with the nitrates. Simply don't dose as much.

What test kit/ test strips are you using?

Edited February 6, 2021 by James Black

[Levi_Aquatics]

You could also try doing 30 percent water changes every week until you get the nitrites and nitrates under control and I agree with @James Black about the fertilizer.

[D Robinson]

Hi all, yes the tank I thought was cycled as it’s been up and running for nearly a year. Nitrates & nitrite showing 250 & 10 on my tetra I done a 100% water change 5 days ago tested the water (after ferts) 20 nitrate 0 nitrite. Ammonia not yet been checked but imagine it’s really high aswell. I have done a constant water change and got everything back to 0 so for now he is safe. Just can’t figure out why the cycle has crashed. I’m using cycled media from my big tank. No ammonia or nitrite in tap water, little bit of nitrates. Thanks

[D Robinson]

Also Feeding a tiny amount of oase organic 2 * per week to try and control waste. 😞 kept tanks for years without issue but this tank has my head battered.

[Will Billy]

There are a few things to consider. Lets begin with your testing method. Are you using test strips or a test kit like API master test kit that uses test tubes and solutions to test your water? Some tests are more accurate than others, while some allow for human error to give false readings. Are you testing before water change? After water change? After water change and adding fertilizer? As James Black mentioned, certain fertilizers will show up in your nitrates. If for a moment we can assume your tests are in fact accurate i would examine your biological filtration. Your bioload seems quite small even for a 30L tank. Even the small amount of livestock excrement and any uneaten food should still provide plenty of ammonia and nitrites to keep your beneficial bacteria well fed and stable. It appears from the picture you have some sort of hang on the back filter ( although im not quite sure the fluffy white thing coming out of the top). It appears you have good water flow which is great for moving those toxins around to feed your nitrifying bacteria (as they dont move around too much). The main 2 causes of disrupting your bacteria cycle are usually #1 chlorine, or chloramine contamination. Are you using a dechlorinator of some sort during water changes? Are you rinsing filter media with chlorinated tap water? Or #2 too aggressive tank maintenance. To many water changes, to much water removed with water changes, constantly replacing filter media (where your bacteria primarily live ). Especially in a small tank with smaller amounts of surface area from plants, decorations, and substrate, it is usually considered a good idea to stager filter maintenance with tank maintenance rather than doing it all at once. By aggressively gravel vacuuming a tank, cleaning decor and glass and replacing your filter media all at once. This wont remove all your beneficial bacteria, but it can cause a drastic drop in bacteria population that can result in an ammonia spike. As your bacteria population begins to grow again the ammonia spike gets eaten and ammonia levels drop, but is followed by a nitrite spike, and then a nitrate spike after that. By staggering filter maintenance you keep your bacteria in your filter when performing tank maintenance, and vice versa you can retain bacteria populations  in and on your substrate and decor while replacing or cleaning filter media. Lets begin there, and see if we can figure this out.

[D Robinson]

Hi Will, I have just used in date API master test kit about an hour ago. Given the issues and massive spikes (off the carts) I performed a constant water change of around 300% with dechlorinated (prime) tap water. Readings are now 20ppm nitrate after ferts (tropica complete), Nitrite 0.25, ph 7.4/7.6, ammonia around 1ppm. I had (now moved to 150L tank) betta and 1 Armano. Yes it’s a HOB filer oversized maxed out on cycled media (cintered glass not weighed) from said 150L, white stuff is filter floss 🙂. Tank around a year old, never vacuumed the gravel but create currents with my hand to sweep up the mess (betta removed obviously). I was using purigen but that’s been removed to see i can get the tank to cycle again. I have a good 1.5 inch layer of fine gravel so surface area for bacteria should be fine in addition to media. Can overdosing prime cause a cycle to crash?

[Will Billy]

Hmm, alright lets dig a little deeper then. First off to the best of my knowledge overdosing prime wouldnt affect your bacteria. Do you know another aquarist or perhaps a fish store you could get a second opinion on your water parameters? I see your ph is 7.4-7.6. That is pretty perfect. What about your gh and kh? I had a friend who had low kh and it caused ph swings. Ph swings are bad for your fish but your bacteria, as in my friends case, is sorta like a canary in a coal mine. Bacteria usually get impacted first from ph swings before livestock. There is even a chance that your water from your water source could have changed. Its not very common, but i have heard of other aquarist remarking on unexpected chemistry changes in their source water. In the meantime till we can sort out the cause of the problem, you can add bacteria like seachem stability, or fritz zyme 7 to try to boost your nitrogen cycle. 

[Streetwise]

Not addressing your specifics, but replacing your synthetic plants with real plants will be beneficial. I always recommend more live plants.

[David Ellsworth]

What is your substrate? You said gravel? You have rock and fake plants so the nitrates are coming from somewhere. If it isn't come from the tap water and you haven't vaccumed the gravel then it could be a build up of organics in the water from waste. If you are battling nitrates I'd look to the substrate, you've checked about everything else.  I'd move the rock and heavily vac the gravel. 

 

Some tanks with live plants can get by without gravel vac because the plants export the nutrients, but with fake plants, you and your water changes are the only export of nitrates. I would try this if you haven't and I completely missed something. 

[D Robinson]

Hi Will, gh is normally around 6-8d and KH is very often close to zero but I use seachem something (sorry forgotten the name) to add KH. But I have often tested the water to find it at zero so thanks I hadn’t even thought a Ph swing could have caused it to crash. I will let the tank cycle again before adding him back in. Thanks for your help!!

[D Robinson]

Hi David / streetwise, before I redone the tank I had plant substrate and easy live plants. Initially it was a shrimp tank but I lost every one of them to the cycle crashing, at that time I put it down to my dechlorinator being off as I would always find chlorine on my test strips. Because of this however I couldn’t keep the algae in check and lost all of my live plants so decided to see if using inert gravel and synthetic plants would help (apparently not) I do use real floating plants (salvinia I believe) this reducing light and exporting nutrients and on the whole is going crazy in the tank. Because I have had the issues for a little over a month I weekly do at least 100% water changes but still finding significant ammonia, nitrite and nitrate and the floaters can’t keep up, I try to feed as little as possible to avoid unnecessary build up of waste. I regularly move the rocks and plants and on the whole there is little waste building up but any that is there I put the HOB on full to pick it up.

[Will Billy]

Well it looks like you might be having a few issues coming together all at once. I would get your kh under control. If you havent gravel vaced your substrate in over a year that could very well be your source. Hob filters do have some mechanical filtration, but when it comes to mechanical filtration a gravel vac is your best friend. Your hob will pull organics out of the water, but only the stuff that happens to float by. On sand substrate it is ok to just surface skim the top as it is such a fine grain it gets compacted enough that organics dont get very deep. With gravel though as it cant compact like sand it has tiny cracks, and crevices that organics can sink down in between. Once it settles down in there your hob will be unable to get it, and it will continue to rot producing ever more ammonia. In a lager tank it may not seem as noticeable, or catastrophic, because there is more water to dilute it, as well as bacteria to handle it. In a smaller tank like your 30L it can get out of hand much faster than your bacteria has time to react or adjust to. Lastly if your test strip is showing chlorine you are getting some cross contamination of untreated tap water from somewhere. Back when i restarted this hobby, after i had successfully cycled my tank and added fish, i went to change out my filter cartridges as part of my maintenance routine. Per instructions on the package of replacement cartridges i “rinsed off” the carbon dust like it stated. Having been out of the hobby for 20+ years, this was my first cartridge replacement, and i did exactly that. I rinsed the filter under tap water and slapped it in. Yep, i totally did that.