Bro the reason no one has answered your question is because it is not complete so they are not able to give you a true and acurate answer!!how big is your grow room ? what type of medium are you using ? what nutes? Etc Etc. we need to know this before you can really say....Peace
yea man, honestly its a bit impossible to answer your question with the info youv provided. get more detailed, and the answers will be more detailed lol
4 plants is too much for one of those tanks imo. I use same set up an two is max for both space and amount of water stored. Just put two in an Lst them