DeFi and compounding can still be tricky with CubDeFi when you invest relatively little, because although the fees are much lower than on the Ethereum network (~$0.50 vs. ~$10), it still represents a large portion of your earnings when you've invested less than $100.

My advice to you would be to put any CUB you earn in the CUB den for now, rather than in one of the liquidity pools. Doing so requires only 2 transactions instead of 4+conversion fee :). And I usually only begin swapping when I've gathered at least 10-20 CUB.