Planted Tank Guru
Join Date: Nov 2009
Location: Missouri united states
I have been running dirt based tank's for a few year's now and believe the underlying issue is that the soil has been exhausted of nutrient's.
Can reset the tank with a mixture of plain topsoil,peat,and clay (I use plain unscented cat litter) and maybe get two year's from this mixture as opposed to a year with soil alone depending of course on plant mass.(Peat an clay help hold nutrient's longer)
Can also dose the water column with dry fertz (aquariumfertilizer.com) and or root tab's, and get even a little more mileage from soil based tank's IMHO.
With a 125 gal tank ,good CO2 distribution /delivery will be tougher than in smaller tank So I might research CO2 injection quite a bit and equipment, before I decided to inject the gas.
CO2 and it's delivery/consistency is said to hardest thing to get right/keep right.
I change 50% of the water in my tanks (low tech) with plant's, about every two week's and clean filter material once a month.
In tanks with young fishes, I change water weekly due to more food's offered to the fry so they will grow faster, and I can trade them off for store credit .
I mix my soil based tanks with 60% soil,40% peat,10% clay or cat litter.
Lighting is low to moderate, and plant's selected accordingly.
I also dose a little of the dry fertilzer's once a week or every other week.
My two cent's.