My first salt water animals were a pair of tank raised Ocellaris and a Caribbean anemone in 1980. I kill them both in short order. I recommend other corals but if, like me, you really want anemone then read the following:
For anemone, you likely not need to do any additive to the water but they need stability. All anemone needs stability temperature, salinity and nutrients. Depends on species, adequate light and current. Some need a sand bed.
Your tank seem new and not have enough light on it right now. If you want anemones consider the following:
Remove the glass top on your aquarium, much better air exchange and temp stability.
Improve light. A good full spectrum LED should be OK. I don't have experience with LED other than Radion. I use MH in the past.
Change water frequently at least for now, 25% every week or two. Make sure the salinity match and temp almost match. 1-3 degree is OK but not 5+ degree in temp different. I have heat new water in microwaves 1 gallon at a time to bring the new water temp up in the winter. Make sure you age the new water at least 24 hr before use it.
With your tank, I would only attempt H. malu (Malu) or E. quadricolor (Bubble tip anemone BTA) for now. They will do OK in a tank that size and does not require a lot of current. Malu needs a sand bed, stay small. BTA is the hardiest of the anemones. Most stay small but some can get really big. Neither are natural host anemone of Ocellaris but in aquarium nearly all of them will go into a Malu and most will go into BTA.
Good luck. Post a thread on the General reef discussion or the anemone forum. I know you posted on WTB but I saw this thread when I check New Posts and though I give you some advices.
