Too many plants to see macros, increase stocking or dose more macros?

[libertybelle]

So my 55 gallon tank is pretty fully stocked (I think? you can see the full list in my profile.) It has been cycled for ages (filter moved from an older tank) but ever since the plants took off I pretty much don’t see nitrates or phosphates.

My plants are all pretty low maintenance (val’s, crypts, whale tail, anubius, hornwort, water lettuce, aponogeton) but some of them grow extremely quickly and despite my stock I pretty much never see nitrates/ phosphates unless I dose them. Considering that this is a low tech tank (medium lighting, no co2), is the goal just to dose enough that macros are not zero? Presuming that if there are “excess” nitrates in the water that’s an indication the plants are able to get what they need?

What about water changes? Do you stretch out water changes if the plants are doing so much of the heavy lifting in the filtration department? I habitually do 30-50% weekly water changes but perhaps that’s overkill and I should just let the plants do their thing and only water change every couple weeks, or less volume.

Would you add stock? In ways that wouldn’t stress the fish for swimming space, of course, perhaps a few mystery snails, adding a few more tiger barbs or skirt tetras to those schools, or a school of cories to chill at the bottom of the tank?

I’m not currently interested in adding co2 and going high tech. I will probably move to dry ferts eventually but for now I’d like to use up what I have which is basically the whole line of seachem liquid fertilizers. I have been dosing “as needed” but now that the tank is a jungle again I’ll be getting back to routine macro and micro dosing.

I’d love to hear what you guys think!

[Caliban07]

Originally Posted by libertybelle

So my 55 gallon tank is pretty fully stocked (I think? you can see the full list in my profile.) It has been cycled for ages (filter moved from an older tank) but ever since the plants took off I pretty much don’t see nitrates or phosphates.



My plants are all pretty low maintenance (val’s, crypts, whale tail, anubius, hornwort, water lettuce, aponogeton) but some of them grow extremely quickly and despite my stock I pretty much never see nitrates/ phosphates unless I dose them. Considering that this is a low tech tank (medium lighting, no co2), is the goal just to dose enough that macros are not zero? Presuming that if there are “excess” nitrates in the water that’s an indication the plants are able to get what they need?



What about water changes? Do you stretch out water changes if the plants are doing so much of the heavy lifting in the filtration department? I habitually do 30-50% weekly water changes but perhaps that’s overkill and I should just let the plants do their thing and only water change every couple weeks, or less volume.



Would you add stock? In ways that wouldn’t stress the fish for swimming space, of course, perhaps a few mystery snails, adding a few more tiger barbs or skirt tetras to those schools, or a school of cories to chill at the bottom of the tank?



I’m not currently interested in adding co2 and going high tech. I will probably move to dry ferts eventually but for now I’d like to use up what I have which is basically the whole line of seachem liquid fertilizers. I have been dosing “as needed” but now that the tank is a jungle again I’ll be getting back to routine macro and micro dosing.



I’d love to hear what you guys think!

Can we see a picture of the tank?

How long has the substrate been down?

Is it possible you have anaerobic denitrification occurring?

It’s definitely feasible for the plants to pull out all the fertilisers. Especially if your lighting is on the brighter side.

[libertybelle]

The filter is older because it came from the tank I upgraded from but the substrate is only like 6-7 weeks old. It’s deeper in the back but probably less than 3 inches while the front is quite shallow.

I have the stock t8 fixture on the front of the tank and added an LED fixture to the back, so the light is pretty bright though I don’t know if it’s technically medium or high. I will say I’ve had no issues with algae control even though I have no CO2 set up.

I suspect the bulk of the fert use is from the water lettuce which I pull out by the handful and the aponogeton / vals which just grow like crazy. If I let things go without trimming for a few weeks my fish will run out of swimming space

[Caliban07]

Originally Posted by libertybelle

The filter is older because it came from the tank I upgraded from but the substrate is only like 6-7 weeks old. It’s deeper in the back but probably less than 3 inches while the front is quite shallow.



I have the stock t8 fixture on the front of the tank and added an LED fixture to the back, so the light is pretty bright though I don’t know if it’s technically medium or high. I will say I’ve had no issues with algae control even though I have no CO2 set up.



I suspect the bulk of the fert use is from the water lettuce which I pull out by the handful and the aponogeton / vals which just grow like crazy. If I let things go without trimming for a few weeks my fish will run out of swimming space

It’s definitely feasible based on that amount of plant mass.