Error running if statements in bash script

Question

Here I have a basic bash script written. I want the if blocks to organize where to write output to. Is there a syntax error with the way I have written my conditional logic? The error I am getting is for every line where I have an if or elif statement. I believe it may have something to do with the -eq comparison operator or possibly a lack or parentheses.

Here is an example of the error I am having (the last errors that occur in the terminal; closest to the bottom):

./lit: line 17: [2: command not found

./lit: line 20: [2: command not found

./lit: line 23: [2: command not found

./lit: line 28: [3: command not found

./lit: line 31: [3: command not found

./lit: line 34: [3: command not found

./lit: line 37: [3: command not found

./lit: line 42: [3: command not found

./lit: line 45: [3: command not found

./lit: line 48: [3: command not found

./lit: line 51: [3: command not found

./lit: line 56: [3: command not found

./lit: line 59: [3: command not found

./lit: line 62: [3: command not found

./lit: line 65: [3: command not found

for i in {0..2};
do
    for j in {0..3};
    do
        for k in {0..3}
        do
            for l in {0..3}
            do

                START=$(date +%s.%N)
                  #some command here
                END=$(date +%s.%N)
                DIFF=$(echo "$END - $START" | bc)

                if ["$i" -eq "0"];
                then
                    echo "test$i$j$k$l $DIFF" >> repeatSample.txt;
                elif ["$i" -eq "1"]
                then 
                    echo "test$i$j$k$l $DIFF" >> writeZeroes.txt
                elif ["$i" -eq "2"]
                then
                    echo "test$i$j$k$l $DIFF" >> repeatPacket.txt
                fi

                if [$j -eq 0]
                then
                    echo "test$i$j$k$l $DIFF" >> byte15.txt
                elif [$j -eq 1]
                then
                    echo "test$i$j$k$l $DIFF" >> byte100.txt
                elif [$j -eq 2]
                then
                    echo "test$i$j$k$l $DIFF" >> byte500.txt
                elif [$j -eq 3]
                then
                    echo "test$i$j$k$l $DIFF" >> byte1000.txt
                fi

                if [$k -eq 0]
                then
                    echo "test$i$j$k$l $DIFF" >> loss10.txt
                elif [$k -eq 1]
                then
                    echo "test$i$j$k$l $DIFF" >> loss22.txt
                elif [$k -eq 2]
                then
                    echo "test$i$j$k$l $DIFF" >> loss37.txt
                elif [$k -eq 3]
                then
                    echo "test$i$j$k$l $DIFF" >> loss50.txt
                fi

                if [$l -eq 0]
                then
                    echo "test$i$j$k$l $DIFF" >> pinkpanth.txt
                elif [$l -eq 1]
                then
                    echo "test$i$j$k$l $DIFF" >> poeee.txt
                elif [$l -eq 2]
                then
                    echo "test$i$j$k$l $DIFF" >> dooors.txt
                elif [$l -eq 3]
                then
                    echo "test$i$j$k$l $DIFF" >> simplehead.txt
                fi

            done
        done
    done
done