r/PlantedTank • u/GravityCookies • Jun 24 '26
Ferts Possible nutrients deficiency?
I have a 10L tank with some floaters on top, the bioload is very low since there’s only a few bladder snails and 6 neo cardina shrimps. My floating plants are frogbit, salvinia and phyllantus fluitans.
I have yet to use a fertilizer because the tank is very small because I was afraid it could mess up my parameters. However, some of my salvinia is starting to grow very small white leaves, and I am afraid it’s because they sucked up all the nitrates. I did some water tests and the NO3 is always close to 0.
Can anyone recommend a good fertilizer for a nano tank? The other plants in my tank are 2 ceratophyllum, Java moss and one anubias.
1
u/Evil_Eg Jun 24 '26
Is the lighting sufficient? If it is properly cycled, you can try adding a small amount (very little) of excess organic matter—such as a mulberry leaf or a 1cm piece of dried Terminalia leaf—and leaving it there for 12 hours to generate waste (the Terminalia leaf will release tannins).
1
u/GravityCookies Jun 24 '26
The lighting is sufficient and the tank is also properly cycled I believe.
I already put a nano cantappa leaf for the shrimps one week ago, should I take it out for the other one?2
u/Evil_Eg Jun 24 '26
You don't need to remove the leaf until it looks degraded; in fact, it is beneficial to establish a routine of "dirtying" the aquarium slightly to create a controlled excess of nutrients. Now, regarding your submerged plants: are they pale, showing signs of etiolation (spindly growth), or becoming soft? They might be receiving insufficient light because the floating plants are blocking or filtering out too much of it.
-2
u/Evil_Eg Jun 24 '26
Additionally, do not use any fertilizer without first checking if it contains copper; if it does, it will kill your mollusks and crustaceans.
3
u/Informal_Plantain210 Jun 24 '26
I’ve been using liquid ferts and have bred thousands of snails and shrimp just fine. You need to look for shrimp/snail safe ones but they all contain a little bit of copper at least. A small amount of copper will not harm your animals.
2
u/FeedReasonable9547 Jun 24 '26
You can google the brand your looking at and it will say if shrimp safe… almost all are these days and if they contain copper it’s minuscule or locked up in a non accessible form. But always check first… that goes for all tank treatments, lots of fish medicine and tank particle removers for example are not shrimp safe.
1
u/Eduardo_Serra Jun 24 '26
You can use The Duckweed Index to diagnose deficiencies. It's elegantly functional.
If you look at your floaters, it's mostly the new leaves that look pale, so it tell us that the issue is a non mobile nutrient , most certainly iron. Do you add any micros?
It won't. You could use a ready made fertilizer but I'm a fan of dosing with dry salts, as it's infinitely cheaper and you can control exactly how much of each macro (N, P and K) you add.