Holes in mini pennywort

[Zoe]

I have this little penny wort plant in my tank - I'm not sure exactly what it's called.  Anyway, it grows like a weed and has nice colour and no algae, but lately more and more leaves (especially the new leaves) are getting holes in them. The leaves don't seem to be dying, but it doesn't look very nice.

It's a 20g long aquarium
2 x 24W T5HO
Fluorite substrate
Two 2L CO2 reactors
Done with blackwater extract and Fluorish weekly
Water changes weekly

Any input would be appreciated!

Zoe

[charlie]

Outside of something nibbling the leaves & not knowing all the details of your tank( other than posted ones), i`m inclined to believe you have some nutrient deficiency, at first thought - Potassium jumped put , but the info you provided suggest it is mostly with new leaves, usually it is said Potassium would be first visible in older leaves, that said it may still be possible Potassium.
Another known deficiency is proper CO2 levels to match lighting intensity - is your light levels driving growth so fast to deplete the available carbon in the water column?
Just a couple of things to consider

[Zoe]

Hi!

Thanks for the insight. To clarify, I have two apistos, 5 cardinals, a misc. rasbora that I got at Big Als by accident with the cardinals, and some oto cats. Would the otos chow down on the leaves if they weren't finding enough to eat? I can give them algae pellets more often.

I also have ramshorn snails, MTS, and some nerite snails, but I don't have an infestation of any of them nor do I see them often on the leaves.

As for CO2, when I had one bottle I had a pH difference of 0.8 between the morning before lights on and at night just before lights out.  I have since added another bottle but I haven't tested recently. Everything else seems to grow well and except for a few small BBA spots, I don't have algae issues.

If you can glean anything further from those additional details I would love to hear your thoughts! If not I will test out the CO2 levels again and keep a closer eye on the leaves of the plants in case something is eating them.

[charlie]

Hi, with the co2 info you provided it would suggest you have that aspect covered.
It may be worth trying some NPK dosing, since Flourish offers very little in that department, i`m guessing the black water extract does not offer NPK either.Given you lighting & CO2 it could very well be NPK deficiency , perhaps your Pennywort type plant is one of the fastest growers in the tank &  may explain why it`s the fist to show the symptom.
Just my thoughts

[Zoe]

Thanks! That makes sense. Is NPK something I can get at B&B Hydroponics?

The wort is definitely the fastest growing plant.  It doubles in size every week or two.

[Fishnut]

If it's not too much trouble, would you mind posting a pic of the leaves Zoe?  I'm just curious what it looks like.

[charlie]

Thanks! That makes sense. Is NPK something I can get at B&B Hydroponics?

The wort is definitely the fastest growing plant.  It doubles in size every week or two.

Yes the NPK can be bought @ B&B
N- Potassium Nitrate - KNO3
P- Potassium Phosphate - KH2PO4
K- Potassium Sulphate - K2SO4 - note there is a fair bit of potassium in the N & P so this one might not be required, just depends on the nutrient demands of your tank, that said Potassium overdose is not known to present any negative effects.
Regards

[Zoe]

I just trimmed it all back so the holey leaves are gone, but it grows back that way I'll snap some pictures for you

Zoe