Please help out a black thumb (water sprite not surviving with Amanos)

[brhau]

Hi,

I run a few low tech tanks, and there's one where I have difficulty maintaining a fast-growing plant. It's a 15-gallon with sand substrate. The floating plants are: Amazon frogbit, Salvinia cucullata, Phyllanthus fluitan. The rooted plants: Echinodorus tenellus, Cryptocoryne wendtii. These are all growing fine, but are relatively slow growing.

I did have a rooted water sprite (Ceratopteris thalictroides) which did well until I started dosing with ferts. I dose to roughly 1/4 EI per week and use Seachem root tabs. Once I started doing that, the crypt melted (and is very slowly growing back) and the water sprite plant started to go downhill.

I also grow water sprite in the 10-gallon tank directly below this one on the rack with very similar conditions, with two main differences: (1) the plants are floating (2) there are no amano shrimp in the lower tank.

Twice, I've taken cuttings from the lower and transferred to the upper tank. One I tried planting the roots and the other I tried floating. In both cases, the plant melts within a week and I can see the shrimp eating it.

The 15-gallon tank is the only one I have with a reasonably deep substrate (about 3 inches) so I'd really like to have some nice rooted plants in there, plus would like a faster growing plant to help with water quality. Questions:

1. Are the shrimp the problem? Are they disallowing the plant to grow by aggressively picking at it, or is it the other way around? (They eat it because it's unhappy.)

2. Any other plants you'd recommend? I've tried growing water wisteria (Hygrophila difformis) in the past with similar results (grows well for a while, then won't grow). Although back then, I only dosed with micros, so it could be different this time around.

Thanks,
Ben

 

[lilirose]

The shrimp are not the problem- they are awesome at cleaning up dead and dying leaves but they won't touch healthy ones. So in fact they're part of the solution, as you don't want the remains of melted leaves in your tank. This is part of the reason people refer to them as "cleaning crew".

Maybe you should try Hygrophila difformis (water wisteria) if you want to try a different easy plant that looks similar. It also is happy to float but grows vigourous roots in sand.

 

[veerserif]

Sometimes fast-growing "bulletproof" stems just don't work in a tank for whatever reason. I've killed every stem of guppy grass I've ever touched. If you can, perhaps just try a bunch of different fast-growing stems (hornwort, pearlweed, guppy grass, water wisteria again, anacharis etc.) ? I got mine from hobbyist swaps or smaller hobbyist-run shops and they're always pretty reasonable for both the price and shipping.

They probably do better floating because of the access to light and CO2 near the surface.

eta: Could there also be a flow issue in the larger tank? That's all I've got for troubleshooting.

 

[kammaroon]

I have Heteranthera zosterifolia growing well in my low tech 45L tank with sand substrate. I dose fertiliser once a week and have to hack it back every 4 weeks or so.