Trying to figure out what nutrient deficiency this is...

[galacticfern]

These spots have developed on my El Nino fern and my Anubias Nana, which causes erosion in the leaves. It doesn't scrub off, it is embedded in the leaf which makes me think it is a nutrient deficiency. My tank is low tech but high light, dosed with Seachem Flourish once a week. pH is a consistent 8.2, with biweekly water changes.

 

[mcordelia]

shot in the dark here, but could it be a plant virus? is that even a thing in aquariums?

i wonder if @AbbeysDad would know...

 

[AbbeysDad]

Black spots on (actually within) the leaves are most often the result of an iron deficiency. You might use a good liquid fertilizer like Seachem Flourish, Thrive, or Aquarium Co-op's Easy Green. It may take weeks for the plant to recover.

 

[StevenF]

with nutrient deficiencies it can be very hard to determine nutrient deficiencies from the visual appearance of plants.multiple nutrient cane cause similar deficiency appearances.

Black spots on (actually within) the leaves are most often the result of an iron deficiency.

Fora iron deficiency typically the leefveins stay green but the rest of the leaf turns yellow. Seachem Flourish (which you are using) uses iron gluconate in the bottle . Iron gluconate is the preferred iron source for your PH but it doesn't last long due to bacterial consumption of the gluconate. So you might want to try the same dose but spilt up in 3 or 4 does during the week.

A chlorine deficiency it the closest thing I have seen to your picture. Yes plants do need chlorine but not in the form of chlorine gas but as a chloride salt. typically tap water has chloride salts. and according to the Vacaville water quality report there should be more than enough in your water. Assuming your are using tap water and doing a weekly water change. Are you and how much water do you change out.?

Any idea as to what your GH(general hardness is of the water? Vacaville appears to get its water from multiple sources so Tap GH could change but based on the water quality report it should be moderately hard.

About the only otherpossibilitiiesI can think of is molybdenum, copper and zinc. Flourish doesn't have much copper but tap water typically has enough due to copper pipes. Flourish relies almost comply on your water for zinc and molybdenum. In my RO water tank I did have zinc and molybdenum issues in the past but I didn't see the dark spots on my Anubias. but I had algae issues at the time. So I probably could n'tsee the spots if I had them.

If you don't want to guess any more do a ICP-Analysis test on your water. I started using it about a year ago. Basically you buy the set kit. fill the container with your tank water apply the labels and mail it out to their lab. And about a week later (assuming no pandemic or postal service delays) you candownload the result from their web site. I can detect 33 elements down to 1 part per billion. It will not detect Nitrogen, Carbon, and has difficulty detecting Manganes. But it does very well with all other plant and animal nutrients. You don't want to see zero ppm on these element plant elements: K, Ca, Mg, P, S, Cl, Fe, Mn, B, Zn, Cu, and Mo, Ni. I can help you go over the results.

 

[galacticfern]

with nutrient deficiencies it can be very hard to determine nutrient deficiencies from the visual appearance of plants.multiple nutrient cane cause similar deficiency appearances.


Fora iron deficiency typically the leefveins stay green but the rest of the leaf turns yellow. Seachem Flourish (which you are using) uses iron gluconate in the bottle . Iron gluconate is the preferred iron source for your PH but it doesn't last long due to bacterial consumption of the gluconate. So you might want to try the same dose but spilt up in 3 or 4 does during the week.

A chlorine deficiency it the closest thing I have seen to your picture. Yes plants do need chlorine but not in the form of chlorine gas but as a chloride salt. typically tap water has chloride salts. and according to the Vacaville water quality report there should be more than enough in your water. Assuming your are using tap water and doing a weekly water change. Are you and how much water do you change out.?

Any idea as to what your GH(general hardness is of the water? Vacaville appears to get its water from multiple sources so Tap GH could change but based on the water quality report it should be moderately hard.

About the only otherpossibilitiiesI can think of is molybdenum, copper and zinc. Flourish doesn't have much copper but tap water typically has enough due to copper pipes. Flourish relies almost comply on your water for zinc and molybdenum. In my RO water tank I did have zinc and molybdenum issues in the past but I didn't see the dark spots on my Anubias. but I had algae issues at the time. So I probably could n'tsee the spots if I had them.

If you don't want to guess any more do a ICP-Analysis test on your water. I started using it about a year ago. Basically you buy the set kit. fill the container with your tank water apply the labels and mail it out to their lab. And about a week later (assuming no pandemic or postal service delays) you candownload the result from their web site. I can detect 33 elements down to 1 part per billion. It will not detect Nitrogen, Carbon, and has difficulty detecting Manganes. But it does very well with all other plant and animal nutrients. You don't want to see zero ppm on these element plant elements: K, Ca, Mg, P, S, Cl, Fe, Mn, B, Zn, Cu, and Mo, Ni. I can help you go over the results.

Thank you so much for your reply! I figured it wasn’t an iron deficiency, and it didn’t look like any other consistent signs or deficiencies Ive experienced in the past or have seen online... I will definitely start dosing more often though based on your suggestion. And yes, my water is consistently pretty hard. I do water changes every other week, about 40-50% changed, then replacement water treated with Seachem prime and a tiny bit of stress coat. Maybe I should be using less dechlorinator? And I’ll look into an ICP test! Didn’t know such a thing even existed, that’s awesome. I was also considering adding a macronutrient fertilizer along with the Flourish, would that be overkill?