Im planning to grow next in coco, which nuts are b...

Okay so the answer you want is any nutrition that is approved for Hydro grow. The more you use a nutrition the better you get with it. So you have tons of options. Vegging NPK Ratio is 3-1-2. Flowering npk ratio is 1-2-3. So you have this information for starters. If you use dry amended nutes you will have to feed multiple times a day. Liquid is easier. You will need a cal mag in coco. The coco always needs to be wet, but not sitting in run off. The coco need a ph of 5.8. So buffer your coco ph prior planting. So a 5.8 in run off is important. If you have a current grow I would start using run off water to start lowering the ph. Even ph buffered coco is not low enough. Then flush coco good prior to start. It uses a lot of water and testing. First feed is 7 days in.

1.3-1.5 EC * left out the important measurement of nute concentration.

any that are made for hydro -- this just means the nutrients are all plant available the moment they go into solution. No fixating, no chelating necessary. microbes donn't help feed the plant, but they still help in other ways - normal flora reduces opportunities for the .01% of microbes that are bad news. 99.9% are fine and their presence means fewer resources for the bad ones. myco is also greatly reduced impact in a soilless grow method and hydro nutes. it may help absorption, but meh. you fertilize every single irrigaiton in soilles. once mature 1.3-1.5 will do most plants well as long as well-balanced ratio of nutes, of course. get 10% runoff (waste water should be sent down a drain or thrown outside but not for use on potted plants) and you won't get any buildup of minerals in substrate if you are religious about it. jack's nutrients GHE pro series is similar* masterblend has a similar 3-part system *they are a bit sneaky and put the micros with the calcium nitrate, which forces you to buy their overpriced micro-fortified calcium nitrate... or you have to supplement those and buy generic cal nitrate locally etc... aka a hassle due to greed. someone thought they were smart in a boardroom somewhere. dry nutes can be a pain to mix, but when you pay $ 0.04 per gallon mixed it's not so bad. a 25lb setup of jack's will mix nearly 3200 gallons. dry amendments can sit in a dry cool place for decades (long shelf life). but the primary thing is that you have 2-3 parts you can adjust and minimize impact to other nutrients. In my exp, N is one of the most fidgity nutes. When i adjust my N due to the plant getting too dark, i only impact Ca (calcium-nitrate), but the micros and all other nutes stay at previous strength. I'm a big fan of that dynamic. There are other ways the allow similar reduced impact while adjusting. avoid the 10-15 part (exaggerating only slightly) nutrient setups.. they are just stealing your money by dividing stuff that could be together. Calcium is sometimes left out because it is most likely to cause a precipitate - with sulfur, i believe. So, you often have to buy that extra or use a setup like Jacks, in which you use calcium nitrate and provide a more than plenty through that 99% of the time. Also why you should always follow any specific instructions about order of mixing... e.g. "other" nutes must be mixed into solution before you dump a bunch of cal-nitrate in.

For effectiveness and ease of use the one part floranova grow and one part floranova bloom are your biggest bang for your buck...

Try floraflex or Athena with additive like purpinator and power si