"I swim at least two hours every day."
Translation:Ich schwimme mindestens zwei Stunden am Tag.
Uhr (specific time), Stunde (time span)! Slaps forehead and gives lingot (for first time ever). Btw, you've now been doing German and/or Spanish (jeden Tag, todos los días) for more than 4 years. May I suggest you consider doing English from German (learning English as if you were a native German-speaker) and English from Spanish? You'll see a lot of German or Spanish words and expressions not found in the German or Spanish for English-speakers.
How about, ich schwimme jeden Tag mindestens zwei Stunden? For starters it is more general time before the more exact, secondly we are not saying at least every day, the everday bit is certain, not sure 100% sure but think my way of thinking makes sense, also am Tag means in the day not every day, guess could also use täglich