[BettahBehBeh]

Hi,

I have a 2.5 gallon mason jar fish tank on my desk at work. I have one betta, one amazon sword, anubias, watersprite, and Brazilian pennywort. All of these plants are small except the sword. They've been anchored in sparse river rock. Tank has a heater but no filter. I moved the Amazon sword from a heavily planted dirt tank that crashed (long story). I'd like to put a Seachem Flourish root tab in the mason jar but don't have a lot of substrate to bury it in and really don't want to cause a water spike that might hurt the fish. I want to keep the sword alive though.

thoughts?

 

[Aqua Aurora]

Your 'substrate' is too large for root tabs or soil. You'd need average or small aquarium gravels or sands. With so much space between rocks for water to get in (with what you have) root tabs will just dissolve and the contents float up into the water column which is not good for the fish or esthetics.
If you want to keep the sword and use root tabs you'll have to change substrates.... However I will say I grow pygmy chain sword (small relative of the amazon sword) in a sand tank with liquid ferts just fine (nothing in soil). I'm not sure how the big amazon sword would handle a liquid fert regime in standard substrates over root based feeding... but with your loose substrate I think it would be able to absorb the liquid ferts through its roots just fine.
What sort of ferts? well Iron is a must for swords, as for the rest.. you need to know your water make up to decide. I use phosphorus, flourish, potassium, and Excel (all from Seachem) with 2x a week iron dose. But depending on what you water contains you may need more of one fert type and less of another.

As a side note, did you re-silicone the valve at the bottom? Some of those jars are known to leak overtime from poor original silicone work. Make sure its well sealed so you don't come in to work to be met with a wet floor and dried out fish.

 

[BettahBehBeh]

thanks for the response. I'll change out the substrate to gravel and use the tabs.