Help with cabomba turning yellow

[Finleyx9]

Planted cabomba about a week ago, and it's been doing great - bright green and has grown about 2" taller. I also dosed with Florish when I planted it, but today I noticed the lower leaves have started to turn yellow. Is this just part of the adjustment process or is there something I should be concerned about?

[coltin]

Can we get some pics of your cabomba? Would love to see how it's looking and maybe get a better idea of what's going on with those yellowing leaves.

[Finleyx9]

Can we get some pics of your cabomba? Would love to see how it's looking and maybe get a better idea of what's going on with those yellowing leaves.

Here's the pic of the cabomba plant.

[Finleyx9]

Still looking for some insight here. The discoloration seems to be progressing, albeit slowly.

[shakinStevens]

Some plant nutrients are mobile, allowing the plant to relocate them as needed. When these nutrients are in short supply, the plant may remove them from older leaves to support new growth, leading to yellowing and eventual death of the older leaves. If left uncorrected, this can result in the loss of all but a few leaves at the top of the plant. Key mobile nutrients include nitrogen, potassium, phosphate, magnesium, molybdenum, and chlorine - yes, chlorine is a nutrient, but plants use chloride salts like sodium chloride, not toxic chlorine gas.

I'd recommend checking a few things:

- Are you using tap water? If so, it was likely sterilized with chlorine by the utility, which should leave behind chloride salts. Molybdenum should also be present in tap water, and plants don't need much of either. If you're using tap water, you likely don't need to worry about Cl and Mo. However, if you're using RO water, these could be a problem.
- What's your nitrate level? You don't want zero nitrate - 5PPM should be sufficient for the plants.
- What's the hardness of your water? A GH test kit can detect magnesium and calcium, both of which plants need. If your GH is low, you might need a GH booster to increase the level. A 2-3 degree increase should be more than enough for plants.
- Phosphate test kits are available, and you only need about 1PPM. Potassium test kits are harder to find.

[stormbrew]

Just cut off the yellow areas, but I'm not sure if that's the root cause. I'd rather figure out why it's happening in the first place.

[Finleyx9]

I'd like to expand on my previous response to help you troubleshoot the issue with your cabomba. As I mentioned earlier, some plant nutrients are mobile, meaning the plant can redistribute them as needed. When these nutrients are in short supply, the plant may remove them from older leaves to support new growth, causing the older leaves to yellow and die.

Given your tap water is treated with Prime, you likely don't need to worry about chlorine and molybdenum. However, your nitrate level is a bit low at 2.5 PPM, especially considering you just did a water change. I'd recommend aiming for around 5 PPM.

Your water hardness is at 10.9 GH and 1.7 KH, which is a good range for most plants. However, it's worth noting that magnesium and calcium are essential nutrients for plants, and a GH test kit can help you detect their presence.

You mentioned you'll check for a phosphate test kit, which is a good idea. Plants only need about 1 PPM of phosphate, so it's not a lot.

I also think the lighting might have been an issue. Your previous LED setup was quite low at 5.5W, and it's possible that wasn't enough for your plants. Upgrading to the Fluval Aquasky 2.0 is a great move, and I recommend continuing to gradually increase the light intensity to avoid any algae issues.