Nitrate poisoning or.?

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Nitrate poisoning or.?

Post by Critterkeeper » Tue Nov 19, 2019 9:58 am


In May I added a perfectly healthy ~10 year old clown loach to a 60 gal tank (I know too small) with another smaller clown loach. Till this past spring I had no idea they could live so long or get so large. The first Loach had been in a 20 gal his whole life (again I had no idea) and he grew to almost 7" alone. I'd sit and have breakfast with him. He was like a dog.

I think I posted here or another loach board about my fear of moving him to the bigger tank and the stress, etc. Took weeks of equalizing parameters and me feeling up to task.

We finally made the transition and all was well untill a few weeks or so ago when I hurt my wrist. I think I wasn't making my regular water changes. Also, the smaller Loach seems more aggressive, and they would squabble over food. That to confess that I was probably overfeeding just so they could find food in separate areas of the tank.

The tank has been healthy and established for 6+ years. Prior occupants with the small Loach were 4 black neon tetras who traded places with big Loach.

Nitrites 0.0
Ammonia 0.0
Nitrates 5-10 ppm (but only after a couple of weeks of daily 20-30% water changes)
Ph 6.5
Temp up to 82

I do believe I had to replace the heater and I know temperature flux can create issues for loaches.

Big loach was showing signs on body of markings like he was brushing up against something in the tank. I could see it below dorsal fin towards tail on his black stripe. Then one day I noticed a vertical red line where base of tail joins body.

I removed most decoration except his tube and cave for other fish so they wouldn't bump into anything during chase. This was about when I tested parameters in several weeks because Fishie had never ever been sick.

First I convinced myself it was an injury from whacking against something during chase. The small Loach pesters him so much I put in a tank divider which lasts for a day or so before they manage to get thru. This gives big Loach a break from small's constant badgering.

In any event I turned up the heat and began water changes. First test was between 20-40 ppm. So we're back down to .5 ish

I bought a uv sterilizer.

I turned up the heat to 84 deg

I started Melafix and got some stress coat.

I researched diseases.

It is not ich.

Perhaps fungal.

Reddening can be nitrate poisoning so I went with that and hoped it would resolve.

Fishie prefers his tube I think to avoid small loach. He is eating and swims well when he comes out.

I working on finding an affordable upgrade to 120 gal. But until then I'm good with daily water changes. Thinking now it may be fungal so I started pimafix. I have a bottle of the green dye medication and some really bad memories of a chiclid so I hope I don't havr to go there.

I'm including the photo. The ghost of perhaps an outline on his black stripe near his tail may or may not be apparent. Again, vascillating between injury/scrape or something fungal. But most notably the tail.

The tail...this is the second week I guess. It looks less angry than it did originally but it's on dorsal/upper body/tail too which was not initially the case.

So. To cap. I'm doing w pimafix now.

I would appreciate opinions on condition and my procedures. I'm loathe to upgrade to that size tank but I don't want to rehome him cause we've been together a long time.

Crikey, it's not letting me post the picture. Will try to asd it to the thread.

Thanks so much.
Last edited by Critterkeeper on Tue Nov 19, 2019 10:20 am, edited 1 time in total.

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Re: Nitrate poisoning or.?

Post by Critterkeeper » Tue Nov 19, 2019 10:06 am

Here's a link to a photo.

Please note small loach not affected.



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Re: Nitrate poisoning or.?

Post by Devid » Tue Feb 18, 2020 6:15 am

Nitrate poisoning is a rare but important cause of poisoning in cattle. It can occur as the result of eating crops such as Brassicas, green cereals or sweet clover that contain high levels of nitrate. However, the most common source is inorganic nitrate fertiliser, either directly (straight from an open bag), via grazing an over-fertilised field, or via water run-off from heavily fertilised fields. Spring is the most common season for nitrate poisoning.

Nitrate poisoning occurs because the nitrate is broken down to nitrite in the rumen. In normal circumstances this nitrite is further broken down to ammonia in the rumen and is then used by the rumen microbes to make protein. However, when large amounts of nitrate are eaten over a short period of time, the nitrite accumulates in the rumen and is absorbed. Once in the bloodstream it reacts with iron in the red blood cells so that they can no longer bind oxygen.
Clinical Signs

The signs are usually seen within a few hours of eating the nitrate. The higher the dose the faster the signs develop.
  • Abdominal pain
    Muscle tremors
    Drooling of saliva
    Blue discolouration of the mouth
    Mouth breathing

The clinical signs are vague, particularly early on. Early veterinary involvement is therefore important. If your cattle have had access to nitrate and start showing signs of illness, get them checked as soon as possible.

Nitrate poisoning can be identified using a blood test for either nitrate or methaemoglobin (the product formed when nitrite reacts with the red blood cells). In severe cases and at PM the methaemoglobin is visible as high levels in the blood result in the blood becoming chocolate in colour


Remove the source of nitrate. Veterinary treatment with methylene blue can be very effective at reversing the changes in the blood, particularly in the early stages.


Prevent access to nitrate sources. In particular, prevent cattle getting into fertiliser stores. Ensiling high nitrate pastures will usually reduce the nitrate levels to safe levels (as will allowing the pasture to set seed). Feeding a high grain diet alongside high nitrate forage has a protective effect because carbohydrates enhance the conversion process from nitrate to microbial protein

The animal can become conditioned to eat larger amounts of feed with a high nitrate content if the increase is gradual. Healthy animals are less likely to be adversely affected than animals in poor health. Adequate amounts of available carbohydrates (grain) allow the animal to consume more nitrate.

Source: ... poisoning/

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Bas Pels
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Re: Nitrate poisoning or.?

Post by Bas Pels » Tue Feb 18, 2020 6:51 am

Assuming your nitrate levels are both accurate en remain as they are, don't be afraid of nitrate poisoning.

This would only happen above 50 mg/l

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Re: Nitrate poisoning or.?

Post by millsn » Tue Apr 14, 2020 4:28 am

His fins look too rounded. Is his tube too small for him?

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