Sulfur smell in substrate - help?
I set up a planted tank in late november and in the last few weeks I've noticed a bit of random plant die off that involved the roots/base of stem basically rotting as well as some fish breathing heavily. For quite some time I thought a few of the fish had gill flukes and I treated them in hospital tanks with PraziPro (in addition to some other medicines in separate cycles just to be safe -- light stuff like Melafix). A few weeks have gone by and I'm positive that no fish are sick, but a bit of heavy breathing persists.
I noticed when doing some aquascaping that the dreaded sulfur smell released as I rearranged some plants... I have read that this can happen if you have too much substrate, or perhaps if it gets overly compacted under large rocks, etc. What can I do about this? I have read that "stirring" the soil can help to prevent this and will do that during my next w/c.
Here is some tank info:
- 1 inch of MGOPS underneath ~2 of black diamond 40-60 grit blasting sand
- decent amount of plants in the tank plus four pieces of driftwood. The d/w is not leeching but one is large enough that it could be compacting the sand (I purposely did not put dirt under the sand in that spot)
- I am basically stocked to capacity with fish, although none are full grown (2 angels, 5 boesemani, 1 apisto, 2 bolivians, 5 sterbai, 2 SAE, large school of tetras)
- I am running one Fluval 406 and setting up a second when it comes in the mail this week
- also running one air pump since I have noticed this issue and it has helped the heavy breathing... though I'm sure my plants don't appreciate it.
- I do a 30% w/c once per week
I think I may just have a bit too much sand in some spots. What do you think?