Holes in the leaves!

[Aqua junky]

Can anyone tell me what could be causing the holes in the leaves?  

[Irene]

They can sometimes be caused by a potassium deficiency or plant-eating fish. I have a really large java fern that was sucking all the potassium out of the water, and it started affected all the plants in the tank. After measuring my tank, turns out I only had 0-5 pm potassium, so I started dosing more and the pinhole problem went away. 

Potassium deficiency in my dwarf aquarium lily

[Angie]

What kind of test did you used?

[Aqua junky]

On 12/1/2020 at 4:16 PM, Brandy said:

 

15 hours ago, Irene said:

They can sometimes be caused by a potassium deficiency or plant-eating fish. I have a really large java fern that was sucking all the potassium out of the water, and it started affected all the plants in the tank. After measuring my tank, turns out I only had 0-5 pm potassium, so I started dosing more and the pinhole problem went away. 

Potassium deficiency in my dwarf aquarium lily

Where did you find a kit to measure potassium?  I've looked online and have thus far come up empty handed.

Edited December 17, 2020 by Nick H.

[Koi]

I wouldn't even worry about a test kit. It could be debatable about how affective most hobby grade test kits are even though I think they aren't just cause of the fact that we have to determine a value off a color chart. That aside, the reason why i don't like these tests are for 2 reasons:

1. There is no definitive way for us to put a value on how much potassium each plant uses. Some plants use more potassium than others and as your plants start growing you might need more ferts than you need a month or two ago

2. I find that more often than not people chase for a certain ppm value of potassium thinking that once they hit a certain ppm threshold, there problems will go away

If you have an all in one fertilizer, I would just up your dose a little and see if in a few weeks to a month if that change has made any progress. 

What you're doing right now I think is a lot better than going out to buy a test kit. Spending time with your tank looking at your plants will give you so much more of a better picture of whats going on in your tank than a test tube ever will. It will take time but eventually you'll be very in tune with what the plant needs and what you need to do to remedy it.

[Blurb]

I find a test has its purpose. it can be helpful with a test value so you can follow the changes in your tank and on the test. How fast it increases or decreases in comparison to the changes you observe in the tank. A reference-point and how it develops. Might not be a general truth, but for a better understanding of your individual tanks development, it can be a good help, I believe.

[Irene]

@Angie @Nick H. I got the Salifert freshwater potassium test kit. It seems to be out of stock everywhere right now (unlike Salifert's more popular saltwater potassium kit), so it might be worth looking at other brands to see if they make freshwater potassium kits. It works very similar to the API GH/KH test kit where you count how many drops of test solution you add, and when the water changes from clear to blue color, then that # drops = x ppm of potassium, according to their chart.

[Koi]

2 hours ago, Blurb said:

I find a test has its purpose. it can be helpful with a test value so you can follow the changes in your tank and on the test. How fast it increases or decreases in comparison to the changes you observe in the tank. A reference-point and how it develops. Might not be a general truth, but for a better understanding of your individual tanks development, it can be a good help, I believe.

I can respect that. Maybe it's because I'm cheap that I see more value in spending my money on other things when I can see if the plants are missing something. My methodology plays a part in my bias since I rather measure the amount of potassium I put in rather than how much is consumed. I just always see people scared of nutrients values in regards to algae where I keep my tank at 20-30 ppm for just potassium and don't see too many problems.

Other than that I have no issue with people inclination to research/study, maybe my inner Scrooge comes out when it comes to limiting expenses

[Jack.of.all.aquariums]

Although lack potassium is often the cause of holes I am suspicious of the fish. Typically potassium deficiency looks like lots of pinholes as if somebody poked it a bunch with a needle.

The fish looks like a a tropheus duboisi. They are herbivores. Normally they munch on algae but I wouldn't be surprised if it was rasping on your plants. It looks like you might have some other African cichlids. Many of them are omnivores so they might be having a nibble too.

[Aqua junky]

If it was my fish I would think the corner of a leaf not little pinholes but who knows