Question of the Day Macro and micro nutrient accumulation in your aquarium - problem or benefit?

[Art]

One thing that doesn't get much talk is the accumulation of macro and micro nutrients in our aquariums. IMHO, it is something that we all should keep in the back of our minds but not obsess about. Nevertheless, it can cause a difference in what you think is in your aquarium and what actually is in your aquarium.

Would this be a reason to test every once in a while?

To figure out what I'm talking about, go to the publicly-available, online calculators (like Rotala Butterfly) or @Hanuman's excellent IFC Calculator and look for the accumulation calculators. Spend some time trying to understand what's happening with you nutrient accumulation based on your husbandry (i.e., water changes and added fertilizer).

A very easy concept to grasp, nutrient accumulation is something @GreggZ talked about in his legendary build thread. Think of it this way. You add 10g of a nutrient to your aquarium. Then you do a water change of 50%. This reduces the amount to 5g assuming nothing else. You then add 10g of a nutrient the next week. That's 15g, then you do a 50% water change to get it to 7.5g. And so on. You see the upward trend that is happening?

Of course, we need to assume that plant uptake will also remove some of it during the week. Likewise, we need to assume that fish food and poop, as well as, other aquarium decomposition (e.g., decaying leaves) will add to the nutrient. There is no way for us aquarists to understand how much uptake there is unless we take a measurement at the beginning of the week and then right before a water change. With a semi-reliable test kit, you may be able to determine a rough estimate. However, that will only be for a few nutrients. Others, well, you just don't know.

Is this accumulation over time bad? Are there some nutrients we should be concerned about accumulation more than others? Is this a good reason to do a full tank reset (100% water change) every once in a while?

We've all experienced a plant that all of a sudden just doesn't recover as well or begins to grow slower than normal. Or, heck, just doesn't look right. We often blame the substrate and pump nutrients into it. Or, we just assume the plant was trimmed too many times.

Could it be that you've hit an accumulation point with some nutrient that is now causing a nutrient problem with your plant?

I would really appreciate your thoughts and experience with this. Again, it may be an area we shouldn't obsess with but it also may be an explanation when no other one is found.

Thanks for reading this far and hanging with me as I try to logically work through this in my head.

Art

 

[BigWave]

I wont get into it right now because it could be a very lengthy topic but every person that has a planted tank should have the basic indicator plants. Ie fine leaved plants like Rotala wallichi, bangladish and Dwarf Hairgrass for Iron. Ludwigia pantanal for Nitrates, and the list goes on and on. As Dennis Wong and Tom Barr say all the time watch your plants!!!

 

[Pepere]

You add 10g of a nutrient to your aquarium. Then you do a water change of 50%. This reduces the amount to 5g assuming nothing else. You then add 10g of a nutrient the next week. That's 15g, then you do a 50% water change to get it to 7.5g. And so on. You see the upward trend that is happening?

Yes, but a 50% water change means you will never exceed twice your dosing.

ie you will never get over 20 g in the above scenario..

 

[GreggZ]

Art you know that this topic is one that I feel is underdiscussed. I went on a crusade a while back to change the way that people looking at dosing. Hopefully some good came of it as most people don't understand accumulation and how it affects water column levels of nutrients.

IMO the main thing to understand is that when someone lists their dosing per week, that can mean wildly different things depending on the amount and percentages of water changes.

There is a simple formula to calculate the theoretical maximum ppm in the water column.

It's the ppm dosed BETWEEN (not weekly) water changes divided by the water change percentage.

So for instance let's say someone says they are dosing 15 ppm of NO3 per week.

At 50% water change once a week the max accumulation is 15/.50= 30 ppm.
At 75% water change once a week the max accumulation is 15/.75= 20 ppm.
At 25% water change once a week the max accumulation is 15/.25= 60 ppm.

Then let's say some is dosing 15 ppm per week but doing two water changes. So that's 7.5 ppm between changes.

At 50% water change twice a week the max accumulation is 7.5/.50= 15 ppm.
At 75% water change twice a week the max accumulation is 7.5/.75= 10 ppm.
At 25% water change twice a week the max accumulation is 15/.25= 30 ppm.

So you can see that when someone says they are dosing 15 ppm of NO3 per week that can mean a lot of things. And if you copy someone's dosing and don't follow the same water change schedule then you are not following the same dosing.

Now this does not take into account plant mass, tank generated nutrients (fish waste, food, dead/decaying plant matter) but it's a good place to start.

Then the next thing to consider is when and how often you dose. I like to keep my water column levels as stable as possible, which is why I front end load all macros right after a water change. I don't want any big dips as some sensitive plants may pout. I can test my water any day of the week and it's pretty much the same reading (TDS too!).

And I strongly agree that every so often it's a good thing to "reset" a tank. Several really large water changes back to back to reset everything. It can cure a lot of problems.

If anyone wants to get into more detail and has the stomach for it I have some posts in my build thread that goes into more detail.

 

[Art]

And I strongly agree that every so often it's a good thing to "reset" a tank. Several really large water changes back to back to reset everything. It can cure a lot of problems.

I have it in my task manager for a reminder every 6 months. I agree it can prevent some of the problems we see on the forums.

I think this may be the post @GreggZ is referring to. It's on front-loading macros.

 

[Firestorm]

This is a very interesting post! Intuitively, it feels right to me to mostly just replenish all-in-one fertilizer for the amount of water changed.

 

[Firestorm]

Full tank reset is definitely an excellent concept to keep in mind!

 

[Ed Wiser]

Another question is when to dose. Should you split a dose over several times during the day. All at once in the morning before lights are on? In the middle of the light period? Or after lights go out?

 

[Firestorm]

GreggZ, I wonder if phosphATE in tap might be different than the Seachem Flourish PhosphorUS that I am dosing. It would make sense that an element (phosphorus) might be much more reactive / have different chemical properties than a compound (PO4).

 

[Firestorm]

Is my nitrate level too high? Several of my platies (born and raised in this tank, never flashed or had clamped fins before) started flashing and have semi-clamped fins (only the dorsal fin looks clamped). I am VERY alarmed, and am trying to figure out the issue. I started CO2 (low rate, ~1.5 drops per min, tank is 40 gal) < 3 months ago, and started dosing Thrive fert (bought back in 2020) conservatively (I usually dose only for the amount of water changed). I also dose a SMALL amounts of Seachem Potassium, Iron and Flourish.

I also recently introduced 5 lyretail swordtails (they went through 6 weeks of QT and were preventatively treated with several rounds of Hikari PraziPro and two rounds of Fritz Expel-P. The swords are not flashing and look well and so does my other fish (five SAEs, oto and a few platies). So, just about four platies look stressed, and about five look fine.

Ammonia and nitrites are at zero (I checked those three days in a row).

Could nitrAtes (looks like they are at ~50ppm) cause distress in the fish? I also started dosing Seachem Phosphorus (about 1/3 of the recommended dose) a few days ago (so this is NEW, this is something that changed just a few days ago) d/t GSA issues.

I wonder if maybe adding five swords dramatically increased a natural amount of nitrate, and thus adding more through Thrive can be an overkill? What do you guys think? Please please advise! My fish pretty much never flashes or has clamped fins as I am always very rigorous about any new fish QT/ anti-parasitic treatment. So, this is very distressing to me, and I must pinpoint the root cause ASAP. Please help!

PS. My tank is heavily planted.

 

[Firestorm]

UPDATE: I know it's not recommended to do huge water changes, but I just felt so distressed and so helpless... So, I ended up changing 10 gallons (the tank is 40 gallon breeder with a thick substrate) and then 30 minutes later, I went with my "gut feeling" and changed another 10 gallons of water (of course, the temperature pf the water was adjusted, the water was dechlorinated with Hikari Ultimate about 22 hours ago). I will not be dosing any ferts for the time being. I went ahead and dosed Tropical Science Fishkeeper. Hoping so desperately that the fish bounces back to good health. Fingers crossed BIG TIME!

 

[Art]

Hey @Firestorm - sorry you are going through that. Always distressing to see your fish not doing well.

My approach is analytical when these things happen. The fact that some of your fish look distressed but others don't likely tells you something about what's going on. In other words, whatever may be off is not at a level that is clearly causing a tank-wide issue. This is good.

Here's what I would recommend to you:

1. Double check the expiration date on your test kits. If they are expired, throw them away. I would purchase quality Ammonia, Nitrate and Phosphate kits. I don't know how you measure pH but a quality pH pen is a good investment.
2. Double check water parameters and post them here.
3. What is your normal water change schedule? I'm assuming you're using tap because you dechlorinate. Are you comfortable that you know the parameters of your tap water?
4. You mention adding quite a few fertilizers. What is your reason for adding these and how much you are adding of each? I think it would be good to reassess what you're doing and why.
5. Nitrate will normally not be a problem for fish unless you get closer to the 100 ppm level and then it may take it being that high for a while before distress is noted. I know this is a debated topic by fish keepers. If you are able to and are curious, you can use something like Poly Filter pads to see if it gives you an indication of what it is pulling out of the water.
6. What type of filter are you using and is it cleaned properly?
7. Do you vacuum your substrate during water changes?
8. The fact that some have a clamped dorsal fin and some don't may indicate the issue may be some sort of disease. I'm no expert nor even reasonably experienced with this but I would do some research and may add some prophylactic medication if I found a possible disease.

Perhaps another member with more fish-related experience can chime in also.

Good luck and keep us posted.

Art

 

[Art]

GreggZ, I wonder if phosphATE in tap might be different than the Seachem Flourish PhosphorUS that I am dosing. It would make sense that an element (phosphorus) might be much more reactive / have different chemical properties than a compound (PO4).

I believe that Seachem's Flourish Phosphorus is KH2PO4 or monopotassium phosphate that is the same as that commonly used by "dry ingredient" gardeners to raise their PO4.

 

[Firestorm]

Thank you for your responses, Art!

To answer your questions: I do use tap water. I never vacuum gravel, ever, as my tanks are always very heavily planted jungles with not half a squire inch left unplanted. I have an Marineland Penguin 200 filter (biowheel is gone, it does NOT have carbon cartridge, but is filled to the brim with filter optimization pads and media). I also have two two-horned sponge filters. I VERY RARELY clean my HOB filter, but every now and again, I do replace the sponges on my two double-horned sponge filters, whenever I'd pull them out to use in QT tank (for new fish QT) and then I never return them back without boiling them first. Since they are not the main filter in my display tank, I never had issues with doing so. Last time the sponges were swapped for new ones was on January 3rd, when I set up two QT tanks for QT my new lyretail swords that were about to arrive in mail.

Of course, I checked expiration dates on the master kit's chemicals, they are good until 2025. I don't know what Poly Filter pads are but will look into it. I strongly suspect that the issue is related to the water, either to a conditioner (Hikari Ultimate) or something else (and I am asking a question about it right below, after answering your questions).

My water schedule was once a week, usually 15 gallons (40 gallon breeder tank with a thick substrate). However, after adding 5 lyretail swords at once (they did go through 6 weeks of new fish QT with preventative antiparasitic treatments of Hikari PraziPro and Fritz Expel-P), I decided to alter the schedule of water changes to ease the tank up into the new bioload. So, my thinking was that for a few weeks, I'd do 10-gal water changes 3x/ week (M-W-F), then decrease to 2x/ week (T-Th), and then eventually go back to once per week. That's when things started to go funky, once I started doing water changes 3x/ week. So, I strongly suspect that the water is to blame. Despite the fact that I've been using Ultimate for months now, this time around (on Friday), I dechlorinated all the water that I'll be using this week with Prime. So, will see if this makes a difference. Last Friday, I did add about 30 drops of Prime directly into the tank, and from what I could tell, it was making thing better. I was working very long hours during the weekend, so did not have much chance to observe the tank.

Despite the fact that I always had heavily planted tanks, I only started injecting CO2 less than 3 months ago. So, I started dosing Thrive (that I bought back in 2020, but hardly used because it seems to exacerbate GSA issues). I dose very conservatively, only about a pump with 10 gal water change. I also very conservatively dose (just a tiny amount) of Seachem's potassium, iron, Flourish (NOT Excel) and as of recently, phosphorus (in hope to help with on-going GSA issue). Last week, when I did all the water changes, I did not dose any ferts because of the situation. But to keep plants alive, I figured I'd be adding 1 pump of Thrive this week with each of the 10-gal water changes, but nothing else.

Here is why I almost never clean my HOB filter:

EXPERT OPINION ON FILTER CLEANING:

I asked a well-known expert David Bogert of aquariumscience.org a question about frequency of cleaning filter pads. What follows was his reply, "The best write up on the problem with cleaning filters of brown gunk is from Swiss Tropicals (one of the few honest suppliers I have found). From the Poret Foam Supplier (Swiss Tropicals) “The brown filter sludge in a filter is for the most part alive and not simply waste. Removing this mud does more harm than good. The purpose of the filter media is not to filter out particles from the water as is often assumed. The media serves as the habitat for a vast array of microorganisms that include bacteria, archaea, worms, ciliates, flagellates, and many others. These microorganisms live in a community that is based on biofilms. The biofilms are created by bacteria that secret extracellular polymeric substance (EPS), which is often called “slime”. The community forms a bioreactor that processes the waste and turns it into food and energy for its members, and ultimately into organic or inorganic products that are then used by plants, evaporate, or removed by water changes. It takes a considerable amount of time to establish this “filter community”; consequently, it is very important not to disturb it unless necessary.”"


QUESTION:
Can a SMALL amount of boiled water irritate fish' skin?

I usually age (after being dechlorinated) my water in 5-gallon buckets. During the water change, in order to match the temperature of the new water to that in the tank, I take a small amount of water out of the 5-gal bucket and bring it to boil to then be added back to the 5-gal bucket, and it matches my tank water down to 0.2 F degree. The exact amount of water to match a 5-gallon bucket to ~79 F is about 3/4 of this kettle, bought and used exclusively for this purpose. Once the water boils or almost boils, I then pour it back to the bucket, mix extra well, double-check the temp and then do a water change. I have two of these kettles, so can do for two buckets simultaneously in order to accommodate a 10-gal water change. Can such small amount of boiled or almost boiled water bother the fish? Does conditioned water experience any significant changes in its chemistry after being brought to boil? Thanks in advance!

Amazon.com

 

[GreggZ]

I never vacuum gravel, ever, as my tanks are always very heavily planted jungles with not half a squire inch left unplanted.

Gravel vacs go a long way to keeping an uber clean tank. Whenever I uproot plants I vacuum the area while the plants are out, and lightly vac wherever I can every water change. Amazing how much gunk comes up and how well plants respond to cleaner condtions.

Of course, I checked expiration dates on the master kit's chemicals, they are good until 2025.

Even a brand new API NO3 kit can be pretty far off. If you really want to know make a calibrated solution to test against. Just saying I would not trust that kit without knowing for sure what it is reading.

That's when things started to go funky, once I started doing water changes 3x/ week.

More water changes will not harm your fish. As long as source water is good you can do a 100% water change. Fish and plants love it.

I figured I'd be adding 1 pump of Thrive this week with each of the 10-gal water changes, but nothing else.

Try to start thinking in terms of NO3, PO4, and K. It's the universal language of the planted tank. One pump of Thrive means nothing as nobody will go look it up to see what it adds.

Here is why I almost never clean my HOB filter:

EXPERT OPINION ON FILTER CLEANING:

I am familiar with that site. I don't care what the "Expert" tells you, keeping filters clean is your friend with a planted tank. He mentions many times he is lazy, and lazy is not good with this hobby. Most beneficial bacteria is in the tank, in the gravel, on the glass, on the plants and decor. In a planted tank you want as few dissolved organics in the water column as you can, and clean well maintained filters go a long way to help. I've seen people see a significant improvement just from cleaning out their dirty filters.

During the water change, in order to match the temperature of the new water to that in the tank, I take a small amount of water out of the 5-gal bucket and bring it to boil to then be added back to the 5-gal bucket, and it matches my tank water down to 0.2 F degree.

You don't need to go to the trouble to match water temps. My normal water temp is about 73*. When I pump up water from my basement storage tanks it drops to about 62*. Plants and fish don't care. You couldn't kill them with a temperature change like that if you wanted to. That being said boiled water is not harming anything.

 

[Firestorm]

Thank you so much, GreggZ!

 

[Firestorm]

A little update:
The lights on the tank went on, and while feeding the fish, I confirmed that all fish was accounted for. Saw my oto, saw all five SAEs, saw all five lyrerail sword girls, both male platies, my blue platy. And although I am not entirely sure of the exact number of my sunset platy females (since they all look the same, all born and raised in this tank), the amount visually looks about right.

Did 10 gal water change today (my tank is 40 gallon breeder with a thick substrate), water pre-treated with Prime on Friday (not Hikari Ultimate, as I did before). Added one pump of Thrive to help my plants a bit through this rough times. The fish looks a lot better. There are still a few female platies that have clamped dorsal fins and flash, but overall, things are looking a lot better.

Probably will continue with my plan to do another 10-gal water change on Wednesday and another one on Friday. On Wednesday, will also add one pump of Thrive for plants. But on Friday, will not add Thrive. Instead, will dose again Hikari PraziPro, just in case. Fingers crossed.

 

[Count Krunk]

Not super sure, as id have to look. But an "incomplete" qt may be the source issue. Of the fish troubles. Just two products doesnt seem like it would cover all the bases.

 

[Firestorm]

Not super sure, as id have to look. But an "incomplete" qt may be the source issue. Of the fish troubles. Just two products doesnt seem like it would cover all the bases.

Thank you! What's "incomplete" qt? If it is incomplete quarantine, then I am not sure that it is because the swords are doing well.

 

[Count Krunk]

Thank you! What's "incomplete" qt? If it is incomplete quarantine, then I am not sure that it is because the swords are doing well.

incomplete just means not covering all the bases of the most common diseases. One could have affected the weaker or more stressed fish, every fish in qt could all suffer from different or multiple ailments, or none. Its why a broad spectrum is covered to be as thorough as reasonably possible.