Restarting a tank - how do I manage ammonia spikes?

[caylentor]

Unfortunately my tank has had a nematode infection leading to a number of lost fish. I've been treating with levamisole but unfortunately it keeps coming back, so I'm going to be restarting the tank completely. This means I'll be getting rid of my substrate, plants and filter media on the advice of the vet.

 

Unfortunately, I don't have another cycled tank to keep my fish in. What can I do to make things as comfortable as possible for them? I have Amano shrimp as well and I'm concerned about their wellbeing.

 

I'll be adding new aquasoil so I'll be expecting an ammonia spike. Is there anything I can do to mitigate the effect on the fish? It will be heavily planted but I remember when I originally set it up there was a lot of ammonia and nitrite in the first few weeks (the fish lived in another tank then so were safe).

 

Is there any way I can save the bacteria in the filter while making sure there's no trace of worms or eggs? This would make life a lot easier if so but I can't think of a way to exterminate the worms without completely sterilising the tank.

 

Any advice would be gratefully received.

[ange]

The best way to deal with ammonia spike in the short term (aside from water changes) is by using a water conditioner* that neutralizes chloramines. This is because the neutralizing molecule can temporarily bind ammonia. In a seasoned tank the goal is for the bound ammonia to be broken down by nitrifying bacteria before the ammonium reverts to ammonia. With a greatly diminished bacterial population the goal will be for your weakened filter to have some additional breathing room to catch up while the bacterial colony populates to the needs of the tank.

Personally I would recommend frequent water changes to remove excess ammonia in addition to dosing the tank with additional conditioner to bind the residual ammonia released by your substrate. If you're not married to the idea of aquasoil, I would recommend making the switch to inert gravel. Aquasoil is generally fine for the first few years and I've used it myself on multiple occasions, but in the long run I've always found myself happier with inert gravel and supplementing nutrients manually. Of course, your mileage may vary which is why I still explained the process you'll likely go through by re-cycling a tank with aquasoil.

Always run an air stone in tanks that are being dosed with conditioner for ammonia control. The product does reduce the dissolved oxygen in the water column and can lead to that classic "fish gasping at the surface" that a lot of aquarists are familiar with. Many companies label their bottle with how much it is safe to overdose but this is more of a guideline than a rule.

Since your vet recommended sending all of your filter media to the shadow realm this is going to be a more difficult process than normal and I'm truly sorry for that. I'm an absolute sucker for sponge filters and love to run one in a tank for a few weeks before starting a new one, but it's definitely a luxury. You may instead find success by using FritzZyme or a similar product, though close monitoring will of course be required while your tank is re-seasoning.

*Water chemistry details here:

• Chloramine is chlorine bound with ammonia. It's commonly added to municipal water systems because it's more stable than chlorine and stays in water systems for a longer period of time while killing germs.
• Dechlorinators such as Prime and Complete are able to remove the chlorine atoms, but are unable to break down ammonia. Note that not all dechlorinators are capable of binding ammonia. Make sure to read your bottle and make sure that it is.
• The way that these dechlorinators work is by removing the chlorine from the water and binding the ammonia (NH3) into ammonium (NH4 ion). This is a temporary reaction that allows nitrifying bacteria to do what they do best and consume the ammonium while it's in a state that's less harmful to fish. The reaction that converts ammonia to ammonium reduces the dissolved oxygen in the water column which is why I recommend running in air stone.

[modified lung]

There's probably no way to save the bacteria without risking some nematodes surviving.

I'm not sure how much and how fast aquasoil leeches ammonia. If it's a lot and fast, it might be a good idea to soak the aquasoil in a separate bucket before adding it to the tank with fish. While that's soaking, you can cycle the filter in tank with the fish and have more control over how much ammonia you add. Otherwise UNS soil doesn't leech ammonia and my plants do really well in it.

The best way by far to fast-track your cycle is to grab a handful of gravel from someone's established fish tank and put it near the intake or if possible inside your filter.

Make sure you pH stays above 7.00 and your alkalinity stays above 3 KH or 50 ppm or your new cycle will severely slow down.

Keep in mind that the higher your pH the more toxic the total ammonia-nitrogen ("TAN" or "NH3/NH4+") that most kits test for becomes.

The most important thing is to watch your fish. If they seem to be hanging near surface, sticking their nose into the air once and a while, or moving their gills rapidly, then there's probably an ammonia or nitrite spike. Ammonia and nitrite make it harder for the fish to breath so the first symptoms are usually related to that. That's also why it's important to make sure your oxygenation doesn't go low during the process.

At a pH of 8 a lot of aquarium fish will start showing obvious symptoms somewhere between 0.5 and 1.0 ppm TAN. At a pH of 7, it's more like between 6 and 7 ppm TAN. But that doesn't mean staying just below those levels are safe, especially for a couple week's time. Luckily you can keep your TAN levels very low and still successfully cycle your tank. I cycle my sponge filters in a week or two at 0.5 ppm TAN in 7.8 pH water.

People have mixed results with bottled bacteria but trying that out won't hurt anything. But make sure the brand has Nitrospira and not Nitrosomonas. Dr. Tim's, Fritz and I think Tetra all do.

Otherwise, keep feed to a minimum, test your water, and water change to keep your fish safe. Most aquarium fish can go at least a week without eating. So skipping a day or three to keep your ammonia under control won't hurt. Biofilm eaters like plecos can go less time though.

In an emergency, you can use Prime. There's a lot of disagreement over whether or not Prime detoxifies ammonia. The people that say it doesn't only base that on chemical theory and ignore the biology of the fish. No one that I know of has done actual tests using real fish, which is what matters, so the truth is we don't actually know if it works or not. But if you're willing to spend the money for a bottle it won't hurt anything.

Otherwise, calcium detoxifies ammonia to a degree. But you'd have to increase your total hardness with a calcium supplement by about 10 °GH or 180 ppm to reduce the toxicity by only 20%. Soft water fish might not like that for long.

If you have a nitrite spike, one tenth of a teaspoon of salt will completely detoxify 1.0 ppm of nitrite-nitrogen, which is also what most kits test for, in 20 gallons of water for most fish.

Good luck.

Edited March 25, 2022 by modified lung

[HH Morant]

There is disagreement as to whether Prime does anything to ammonia or nitrites. See my post "hold my beer while I detoxify this" and the responses. You can find it by using the search function.

Of course detoxifying ammonia would be inconsequential unless nitrite is also detoxified, so Prime - and some other de-chlorinators - claim to do both, a remarkable chemical feat. In fact, most de-chlorinators now claim to at least detoxify ammonia. Each manufacturer apparently has a secret formula.

The best way to protect your fish during an ammonia or nitrite spike is to test regularly and do water changes until there is enough beneficial bacteria to do the job. I believe that is really the only way. I don't care if you spend money on a product that doesn't do what it claims. It's your money. But if believing that ammonia  or nitrite is detoxified causes you to decide not to do a water change, that could hurt or kill your fish. 

[caylentor]

Thank you all for the comments!

 

I've got some aquasoil already that I didn't use last year - that's now in a bucket with some dechlorinated water to see if I can get at least some of the ammonia out of it. My tank sits around 7.2 pH so unfortunately ammonium will convert to ammonia.

 

I use Prime as a dechlorinator as standard, though I would absolutely be monitoring the tank daily and changing if I see any ammonia or nitrites, I just wondered if there was any possible way to avoid putting the fish and shrimp through the stress but it doesn't seem likely unfortunately if I have to lose my bacteria colony.

 

Feed wise I have fry that are very newly hatched so they're currently getting fed BBS every few hours, though in small amounts. Do fry need a seasoned filter? If not I could relocate them to my hospital tank temporarily but it doesn't have an active filter.

 

We have a friend relatively close by with a tank, admittedly very different setup and fish, but would that make a difference or would some of their media be ok?

 

I'm running an airstone all the time anyway at the moment as I've been having quite a bad protein film forming on top of the surface so at least that's taken care of.

 

Thank you again!

[modified lung]

On 3/26/2022 at 12:49 AM, caylentor said:

Feed wise I have fry that are very newly hatched so they're currently getting fed BBS every few hours, though in small amounts. Do fry need a seasoned filter? If not I could relocate them to my hospital tank temporarily but it doesn't have an active filter.

Fry are usually a little more sensitive than adults so a seasoned filter or some kind of surface area is a good idea. But if that's not an option, then whatever tank has more water to dilute the ammonia is better. Or more frequent water changes work.

On 3/26/2022 at 12:49 AM, caylentor said:

We have a friend relatively close by with a tank, admittedly very different setup and fish, but would that make a difference or would some of their media be ok?

The closer to your parameters and setup the better but gravel from any kind of seasoned tank will speed your cycle up by a lot.

[AquaHobbyist123]

I use Seachem Prime, which also neutralizes ammonia and nitrite. Super useful.

[jwcarlson]

For such a small tank you can easily change 50% of water per day (or even twice a day) for quite some time before it becomes a major pain.

Additionally, Fritz Zyme 7 does a pretty good job of jump starting cycles (in my experience).  It won't prevent the nitrite spike, but the bacteria eating ammonia colonizes pretty quick comparatively.  I did a fish-in cycle with my discus tank in February, changing 55 gallons in the 75 gallon tank every night (with a big bottle of Fritz Zyme at the beginning).  Using Prime to dechlorinate (and maybe help with whatever might still be in the water).  Changing water will slow the cycle down, but it will eventually cycle.  The discus tank took about 5-6 weeks to totally cycle, I think.  No noticeable problems with the fish (related to cycling), they grew 1/2" a month during that time.  Edit to add that I also did the recommended dose of Seachem Stability after every water change on the discus tank.  This method was suggested by some old-timey discus keepers and it worked really well.  Big daily changes + Prime + Stability.

Did the same with a 10 gallon at the end of last year (but didn't use Stability).  The 10 gallon took about two weeks or so.  In a pinch, the Tetra starting bacteria also seems to do pretty well on the 10 gallon.  It might at least get you over the ammonia hump.  50% water change in a 10 gallon tank takes almost no time, I just set up a bucket next to the tank and filled it after the change.  Used a spare heater to heat it and an air stone to offgas my CO2 and age the water (mine goes from a pH of 7 to 8.2 or 8.3 when aged).

Edited July 6, 2022 by jwcarlson

[AquaHobbyist123]

Seachem Stability is also good