Nitrate And Phosphate Levels For Low Tech Set Up

[Miss Wiggle]

been running my little 10gal as a low tech set up, it's just full of weeks like ludwigia and hygrophilia at present, 2wpg, no Co2, overstocked to provide fertilisation.

I'm 'lucky' in that our tap water nitrate is 0, which is excellent for some tanks but not for this one. I've also got a trickle filter which is very good at removing nitrates.

so despite not having done water changes for about 3 weeks now (it's killing me, really it is) my nitrate reading is barely hitting 5ppm, and phosphate is at 2ppm.

are these levels going to be OK for basic slow plant growth or should I try and bump them up somehow.

 

[Themuleous]

Those levels are fine, for low light tanks its not nearly as important and you have detectable levels so the plants will be able to get what they need. The most important thing in any tank is not necessarily how much you have, but that the levels are stable.

Sam

 

[Miss Wiggle]

ok, i'll monitor them for stability and see how much if at all they are fluctuating.

 

[plantbrain]

Well, depending on the food you feed, the ratio of NO3 and PO4 will change.

So some tanks might have 20ppm NO3, and 0ppm PO4.
Typically, they have 0 ppm of NO3(ask yourself why that might be) and .5-2ppm of PO4.
Fish waste is generally NH4, then NO2, then NO3.

If you have very low limiting NO3 levels, then any NH4 that's produced by a small no# of fish will be uses asap.

You can add some K2SO4 and traces once a week, maybe some Ca/Mg.
If the tank is healthy and getting to the 2-4 months stage, time to add a little KNO3(once a week, maybe 3-5ppm).
Same thing with PO4, at about .2ppm or so.

Regards,
Tom Barr

.

 

[Miss Wiggle]

in English please Tom? didn't understand a word of that sorry!!!

i've been adding some flourish which ian tells me is basically trace roughly once a week but my eventual aim is to just use the fish as fertilisation.

the tanks very mature it's about 1.5 years old, but has only been in it's current form for maybe 2 months tops.

 

[plantbrain]

Haha,

I knew I'd get a response on that one hehe.

Basically you can have a very low level of either or both NO3 or/and PO4.

And that's okay.

Why?

The rate of growth is relatively slow in a low light, non CO2 tank.

So the nutrient demand is also slow, so the fish waste can balance with the plant uptake/demand etc for plant growth.

That's the beauty of a non CO2 planted tank.

You can add a trace amount of KNO3, KH2PO4 to add some K, NO3 and PO4 maybe once every 1-2 weeks, but not much at all, just a small smidge.
Same with traces, once a week, maybe 1 ml per 50 liters.

Add lots of algae eaters, Otto cats. SAE's, Amano shrimps.
These will be a lot more effective per critter in a non CO2 aquarium.

I think Richard at AE has a GH booster, similar to what we developed here State side, you can also consider adding about 1/8th teaspoon once every 1-2 week per 100 liters of tank.

Regards,
Tom Barr

 

[Miss Wiggle]

ok, seems to be working out well on this tank, with Co2 i had massive algae issues and now it's all but gone. got a few ottos and amano shrimp in there who are doing a great job of keeping things sparkling.

slowly but surely my plants are growing nad i'm doing bugger all to the tank except feeding and monitoring nitrate levels as I'm gettng a bit twitchy about the lack of water changes. I'm a stickler for them usually, all the other tanks get at least 50% weekly. So it's worrying me a bit to not be doing them. I just have to keep reminding myself it's not neglect, I'm not doing them in a measured controlled way!

why would I need a GH booster? don't even know what my GH is tbh although I expect Ian knows what our tap waters like.

 

[Dave Spencer]

ok, seems to be working out well on this tank, with Co2 i had massive algae issues and now it's all but gone.

Adding CO2 greatly accelerates plant growth and, therefore, nutrient demands, even in a low light tank, but to a lesser degree. I suspect that whilst you were adding CO2 your plants were growing more and becoming nutrient deficient, allowing algae in through the back door.

why would I need a GH booster? don't even know what my GH is tbh although I expect Ian knows what our tap waters like.

GH booster will add Ca and Mg to cover any potential deficiencies in your tap water. I think most tap water in the UK has plenty of Ca, but Mg levels are a little unknown to me. I add a pinch to my tanks at water change just to cover any potential Ca/Mg deficiencies.

Dave.

 

[Miss Wiggle]

what should my levels of Ca and Mg be? we've got SW test kits for both these elements althiough i'm not sure if they work on freshwater i may be able to test and see if i actually need to increase them.

i don't like adding anything to my tank that's not needed, liek to know what the levels are before i start putting more in.

 

[Dave Spencer]

It may well be that your tap water has all the Ca and Mg that your tank needs. I only add a small amount at water changes because I don`t know the Mg levels, although I could find out if I felt inclined. I`m not trying out anything particularly scientific, just covering all the bases safe in the knowledge that I am not adding huge amounts of Mg. When you look at what Tom is suggesting you try, there is no exact science involved here, just a blanket to cover everything in a relatively controlled manner.

With a low tech tank such as yours, I wouldn`t get too bogged down with testing. I think there may be a correction factor using SW kits, but I am not at all sure about this.

Try the regime that Tom has suggested, but ultimately let your plants tell whether things are OK and adjust accordingly.

Dave.

 

[Miss Wiggle]

OK I'll think about adding a gH booster. want to give the tank a good chance to settle into the current routine before i start making changes. as the tan is new and therefore relativley unstable i've no real way of telling if changes are sucessful or not so i need to let things clam down before i try changes.

 

[plantbrain]

I think many things about planted tanks require some understanding that deviates from the norms and conventions we were taught as fish only aquarists.

Some, like large weekly water changes using say EI, works great and to our advantage.

But EI targets a particular goal.
And thus has the large water change trade off for less testing/good fish health/some reduction in optential accuracy, but you can increase the water change % and frequency and /or use stok solutions instead of teaspoons etc for higher accuracy.

Depends on your goal and which combination of trade offs works best for your goal.

Since you are using a non CO2 method, and you have noted a reduction in algae, the gaol has changed.
Now the goal is balanced tank needs, with the plant's demand for nutrients/CO2 = the fish waste.

In reality this works pretty well.
But we can still agument this a little without hardly any effort on our part by adding a little tiny bit of nutrients every 1-2 weeks.

Still, the main tenets and goal of a non CO2 method is no testing, little pruning work and no water changes.
The no water changes seems at first a problem.

But...........

If you have a decent fish load, and you are not adding PO4/NO4 from fertilizers other than fish food, the demand is not great.

Over time the plants adapt very well to low CO2.
This can take a few weeks but thereafter things really settle in and these tanks are amazing.

When we do large frequent water changes, the tap water and the exposure of the plants to the air essentially "confuses" the plant. These add large amounts/increases in CO2.

If the CO2 is stable, whether it's high with adding CO2 gas,or without any water changes in a non CO2, then the plants can adapt very well and the algae do not respond.

Changes in CO2 ppm are a good signal if you are an algae spore waiting for ripe conditions to grow.

Plants use a large enzyme to grab and use CO2. This cost a lot to build and make for the plant and plants cannot do this rapidly to meet the demand if things change rapidly.

When the CO2 is high, they stop making so much of this enzyme and get "lazy". So there is not much around.
Then we come along and forget to clean a filter/poor circulation from a huge increase in plant biomass, clogged CO2 disc etc................and the CO2 ppms drop a lot, then the plants stop growing because now they very very little of this CO2 enzyme.

They have to make more to grow in a low CO2 tank. This takes several days/weeks to make enough and redo thier entire metabolism. Algae sense this and start to grow if this goes on too long.

If we bob back and forth from low to high, then we get algae.

This explains why there is no algae in both high and low CO2 planted tanks as well as why we should not do water changes in non CO2 tanks.

Which is really a great thing as neglect, little pruning, no testing, and no water changes are awesome goals for many of us!!

The other option is using less light and CO2 + water changes.
This gives the most wiggle room since less light = less CO2 demand, less nutrient demand and more flexibility in the time to dose and CO2 ppms.

As you add progressively more and more light, these become progressively more critical(CO2/nutrient levels), thus they are pprportional to light intensity.

I do find it odd, that many suggest limiting nutrients, fevorant testing and gloom and doom etc if you do not, yet have never bought a light meter nor measured light

Light, unlike CO2/nutrients, is very stable and thus makes a good place to modify and change growth rates of our plants.
But the books, and articles suggest you need more light for many plants(which is not true).

Then when folks have a rough time with high light and algae, they give up in the hobby.
But most succeed with with non CO2, things just grow slower and and you use much less light because here, they rarely suggest high light and that CO2 gas.

The plant biomass assimilates the fish waste into ore plant biomass in such tanks and thus the water is very ppure, and the nutrients are about as low as you can get them without doing water changes.
Plants can handle super low nutrient levels when your plant growth rate is also slowed down 10-20X to that of a CO2 gas enriched tank!

Make sense?

It's all about the rate of growth.
That's why folks have several methods to grow plants that all work.



Regards,
Tom Barr

 

[Miss Wiggle]

just about makes sense Tom! really do appreciate your contribution.

as you've said it does depend on your goal. i want low-maintenance. but the idea of no maintenance is pretty scary for me. see for me on my other tanks, feeding the fish and doing a 50% water change weekly is low maintenance, takes next to no time really.

its like when i got our marine tank and found out about filtration through Live Rock. The idea of not having a standard bit of equipment called a 'filter' on your tank is absolutely horrifying in a way! Now I'm used to it I wouldn't have any other way.

I just think I'm a bit of a control freak, I'm happy for the tank to run itself, i just wanna check up and make sure it's doing a good job

So while I don't intend to be testing a lot on this tank long term, I'm happy to do a bit now, keep an eye on things while I get the balance right.