Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
Test the GH in the water.
GH is a combination of Calcium and Magnesium.
If it is any lower than about 3 German degrees of hardness, then there is likely a deficiency.
Also, get a fresh water Ca test. Look up the formula and you can tell how much of the GH is Mg and how much is Ca. (the formula is not simply GH - Ca = Mg)
It should be pretty close to a ratio of 4 parts Ca to 1 part Mg.
If is it not, then supplement with Calcium chloride to raise the Ca or with Epsom salt to raise the Mg.
If both Ca and Mg are too low (GH under 3 degrees) then use GH booster such as Seachem Equilibrium to raise both.
Next, what is the pH in this tank?
Acidic water will erode snail shells. pH should be about neutral or more alkaline (about high 6s on up) for snails.
You can control the pH by controlling the carbonate levels.
If the pH is too low, then raise the KH and this ought to raise the pH.
Also, look into what is keeping the pH so low, and fix that.
Decomposing organic matter, tannins and other organic acids from driftwood and CO2 are the biggest things that lower the pH in an aquarium. Water changes to remove the fallen leaves and tannins will help. Replacement water should have GH and KH where you want the tank to be to begin correcting it in that direction.
If the tank is being run for fish that thrive in soft, acidic water then you do not want to raise the GH, KH or pH. So do not keep snails in this tank, and remove plants that are showing deficiencies in this water.
Soft water fish can usually handle GH of up to 3 degrees, and a degree or two of KH. This would keep the pH in the low to mid 6s. This is probably not enough to keep MTS shells intact, but should be enough to prevent Ca deficiency in the plants.