The Planted Tank Forum banner

Valisneria turning white

335 0
Hi everyone,
Longtime lurker first time posting. I’ve been keeping fish and plants for ages, but I’m pretty new to keeping plants in the fish tank :)

So, my new growth on the valisneria is white/transparent. Not melting or stunted or anything, just growing in white. All the new runners, as well as the bottom third or so of the older plants leaves. It doesn’t seem to be spreading/rotting, it just l the new growth is lacking chlorophyll.

Tank parameters: (short version)
30 gallon
Lights: 2, 13 watt 1600k CFL bulbs (about 28 lumens per liter) it also gets some sunlight through an east window. I’d consider it ‘medium’ light.
Substrate: 1/2 inch of soil (50:50 mix of red clay garden soil and worm casting compost) capped with 1.5-2 inches of pool filter sand.
PH: 6.8-7.2
Hardness: medium-hard (100-500 ppm with a dipstick)
Livestock: 8 leopard danios and 5 WCMM.
Plants: 40-50 adult valisneria and the same amount of baby (1-2 inch tall) crypt wendetii.
Fertilizer: none
No Co2 and no plans to get any in the future.

Tank parameters/history: (long version :)

I setup the tank in August. No filter, no livestock, just 5 valisneria and a bunch of tiny (less than 1”) crypts I had from a mother plant.
The soil/compost mix was capped with 1” of pool filter sand. The intention was to let the soil leach/stabilize before the livestock were added.

During this time I had some pretty server green water, but the plants seemed to be healthy and growing. I did weekly 30-50% water changes with ‘used’ water from a mature fish tank to help add nitrogen and fertilize the plants.

After a few months the green water had reduced to just a light haze and the valisneria had expanded from the original 5 to around 40 adult plants with more on the way. I trimmed every few weeks and some of the plants were over five feet long!!
I added the fish about a month ago. Before adding them I did a 90% water change and added another inch of pool filter sand to hopefully keep in any lingering soil leaching that was causing the green water.

I installed a HOB filter with carbon (I just added the carbon temporarily to get rid of lingering tint from the soil, I swapped it for a sponge after two weeks) I also added a sponge filter that had been maturing for over a month in a (slightly overstocked) 20 gallon tank for an ‘instant cycle’.

Within a week of adding the fish and filtration the remainder of my green water disappeared and the tank is now crystal clear and looking good.
The fish also seem to be healthy, and the danios have actually spawned twice.
Since adding the fish I do weekly 30-50% water changes using clean water.

But over the last few weeks all the new valisneria shoots are coming in white. I’m a bit stumped since they have been growing well/fast/healthy up until now.

The white growth seems correspond with the green water clearing up, so could it be do to lack of nutrients? Is it a deficiency? A reaction to the increased water movement? Is it possible the runners are not getting their roots deeply enough through the additional sand so they are not rooting in the soil?

I’m thinking about starting to fertilize but I was hoping the bioload from the fish and minerals from the soil would be enough for a while, and I don’t want to add nutrients that I don’t need yet.

Any thoughts and advice would be appreciated. Thanks for reading!