So I'm making reasonably good progress with my 65ltr planted "learner tank" - thanks for the help so far (most of which has been just from reading other's posts) I've got my head around lighting (this is low light/low tech, no C02 ... yet), water flow, basics of ferts, and plants are growing fine but not yet thriving, but I've at least got my algae issue under control, and I've just started adding fish (3 male guppies from my other 120ltr non- planted tank, and two amano shrimp).
I'm in the process of getting to know more about my water parameters, and while learning about working with my low tapwater KH, keep coming across posts/articles that suggest I might have a calcium deficiency effecting both fish and plants in both tanks.
My question is about ways to add calcium that might serve simultaneously to nudge up my KH for buffering, act as a micro supplement for plants and fish, and ensure my shrimp have enough for their shells. Calcium carbonate as crushed coral seems to be the most popular suggestion for buffering purposes (other than bicarbonate soda, obvsly), but I can't figure out where to put them. My substrate is in and planted, and I don't have chambers in my filter (in fact it's already got a bunch of ceramic rings from my 120gal wedged in there to support cycling) I saw a post suggesting pharmaceutical calcium carbonate, but my local pharmacist tells me all their products have additional ingredients, which feels a bit wild card for me. Which leaves crushed limestone, or limewater, research for which is sending me into the world of marine aquariums, which are a bit over my head. I am struggling to find anything on ingredients in commercial buffering and marine compounds. All I've learned so far, really, is that there are good reasons for why one should be cautious about adding any chemical to your tank!
Anyone got ideas for a good starting point to learn more about adding calcium and calcium carbonate in freshwater tanks?
My water comes out of the tap at ph 7.5, GH 3, KH 0. My non planted 120ltr is currently ph 7, kh 1, gh 4.5. My planted 65ltr is ph 7, kh 3, gh 4. The higher GH/PH are due to some experiments with buffering I was trying out last week, which have not yet fully dissipated from water changes. Not entirely sure what's boosted it in my 120ltr, though it is just clearing a salt treatment with some eSHa minerol added.
Calcium concerns are leaf curl on new growth of my ludwiga repens in the planted tank, and some issues with rickets in my guppies in my 120ltr. I'd previously assumed this was down to genetics, and was culling fry as soon as I saw it in them, but one site suggested it could also be deficiency in vit d, calcium or potassium. The shrimp are fine so far, but then I've only had them a week.
I alternate King British flakes and Hikari guppy pellets, with blanched peas once a week, for the fish. Shrimp have also been getting some Hikari shrimp pellets to supplement their algae munching. I've been using Tropica Premium (micro ferts) for the plants for now - until I can get a better understanding of mixing dry frets. It's not ideal - I'd planned to add fish sooner for macros, but then noticed some health concerns I thought might be parasites- hence them getting a salt treatment in the bigger tank.
Sorry if this is long. And thanks in advance for your help!