diff --git a/tig-protocol/src/contracts/benchmarks.rs b/tig-protocol/src/contracts/benchmarks.rs
index 08f211ba..bf86e4dc 100644
--- a/tig-protocol/src/contracts/benchmarks.rs
+++ b/tig-protocol/src/contracts/benchmarks.rs
@@ -40,15 +40,6 @@ pub async fn submit_precommit<T: Context>(
         return Err(anyhow!("Invalid challenge '{}'", settings.challenge_id));
     }
 
-    // verify min nonces
-    let min_nonces = config.benchmarks.min_nonces[&settings.challenge_id];
-    if num_nonces < min_nonces {
-        return Err(anyhow!(
-            "Invalid num_nonces. Must be at least {}",
-            min_nonces
-        ));
-    }
-
     // verify algorithm is active
     if !ctx
         .get_algorithm_state(&settings.algorithm_id)
diff --git a/tig-protocol/src/contracts/opow.rs b/tig-protocol/src/contracts/opow.rs
index 4d8138d8..a799c61b 100644
--- a/tig-protocol/src/contracts/opow.rs
+++ b/tig-protocol/src/contracts/opow.rs
@@ -128,111 +128,129 @@ pub(crate) async fn update(cache: &mut AddBlockCache) {
                 frontier_indexes.insert(point, frontier_index);
             }
         }
-        solutions.sort_by(|(a_settings, _, _), (b_settings, _, _)| {
-            let a_index = frontier_indexes[&a_settings.difficulty];
-            let b_index = frontier_indexes[&b_settings.difficulty];
-            a_index.cmp(&b_index)
-        });
+        let mut solutions_by_frontier_idx =
+            HashMap::<usize, Vec<(&BenchmarkSettings, &u32, &u32)>>::new();
+        for &x in solutions.iter() {
+            solutions_by_frontier_idx
+                .entry(frontier_indexes[&x.0.difficulty])
+                .or_default()
+                .push(x);
+        }
 
-        let mut max_qualifiers_by_player = max_qualifiers_by_player.clone();
-        let mut curr_frontier_index = 0;
         let challenge_data = active_challenges_block_data.get_mut(challenge_id).unwrap();
         let prev_solution_ratio = active_challenges_prev_block_data
             .get(challenge_id)
             .map(|x| x.average_solution_ratio)
             .unwrap_or_default();
         let min_solution_ratio = prev_solution_ratio * config.opow.min_solution_ratio_factor;
-        for (settings, &num_solutions, &num_nonces) in solutions.iter() {
-            let BenchmarkSettings {
-                player_id,
-                algorithm_id,
-                challenge_id,
-                difficulty,
-                ..
-            } = settings;
+        let min_num_nonces = config.opow.min_num_nonces;
+        let mut player_algorithm_solutions = HashMap::<String, HashMap<String, u32>>::new();
+        let mut player_solutions = HashMap::<String, u32>::new();
+        let mut player_nonces = HashMap::<String, u32>::new();
 
-            if curr_frontier_index != frontier_indexes[difficulty]
-                && challenge_data.num_qualifiers > config.opow.total_qualifiers_threshold
+        for frontier_idx in 0..solutions_by_frontier_idx.len() {
+            for (settings, &num_solutions, &num_nonces) in
+                solutions_by_frontier_idx[&frontier_idx].iter()
             {
+                let BenchmarkSettings {
+                    player_id,
+                    algorithm_id,
+                    challenge_id,
+                    difficulty,
+                    ..
+                } = settings;
+
+                let difficulty_parameters = &config.challenges.difficulty_parameters[challenge_id];
+                let min_difficulty = difficulty_parameters.min_difficulty();
+                let max_difficulty = difficulty_parameters.max_difficulty();
+                if (0..difficulty.len())
+                    .into_iter()
+                    .any(|i| difficulty[i] < min_difficulty[i] || difficulty[i] > max_difficulty[i])
+                {
+                    continue;
+                }
+                *player_algorithm_solutions
+                    .entry(player_id.clone())
+                    .or_default()
+                    .entry(algorithm_id.clone())
+                    .or_default() += num_solutions;
+                *player_solutions.entry(player_id.clone()).or_default() += num_solutions;
+                *player_nonces.entry(player_id.clone()).or_default() += num_nonces;
+
+                challenge_data
+                    .qualifier_difficulties
+                    .insert(difficulty.clone());
+            }
+
+            // check if we have enough qualifiers
+            let player_solution_ratio: HashMap<String, f64> = player_solutions
+                .keys()
+                .map(|player_id| {
+                    (
+                        player_id.clone(),
+                        player_solutions[player_id] as f64 / player_nonces[player_id] as f64,
+                    )
+                })
+                .collect();
+            let player_qualifiers: HashMap<String, u32> = player_solution_ratio
+                .keys()
+                .map(|player_id| {
+                    (
+                        player_id.clone(),
+                        if player_nonces[player_id] >= min_num_nonces
+                            && player_solution_ratio[player_id] >= min_solution_ratio
+                        {
+                            max_qualifiers_by_player[player_id].min(player_solutions[player_id])
+                        } else {
+                            0
+                        },
+                    )
+                })
+                .collect();
+
+            let num_qualifiers = player_qualifiers.values().sum::<u32>();
+            if num_qualifiers >= config.opow.total_qualifiers_threshold
+                || frontier_idx == solutions_by_frontier_idx.len() - 1
+            {
+                let mut sum_weighted_solution_ratio = 0.0;
+                for player_id in player_qualifiers.keys() {
+                    let opow_data = active_opow_block_data.get_mut(player_id).unwrap();
+                    opow_data
+                        .num_qualifiers_by_challenge
+                        .insert(challenge_id.clone(), player_qualifiers[player_id]);
+                    opow_data
+                        .solution_ratio_by_challenge
+                        .insert(challenge_id.clone(), player_solution_ratio[player_id]);
+
+                    sum_weighted_solution_ratio +=
+                        player_solution_ratio[player_id] * player_qualifiers[player_id] as f64;
+
+                    if player_qualifiers[player_id] > 0 {
+                        for algorithm_id in player_algorithm_solutions[player_id].keys() {
+                            let algorithm_data =
+                                active_algorithms_block_data.get_mut(algorithm_id).unwrap();
+
+                            algorithm_data.num_qualifiers_by_player.insert(
+                                player_id.clone(),
+                                (player_qualifiers[player_id] as f64
+                                    * player_algorithm_solutions[player_id][algorithm_id] as f64
+                                    / player_solutions[player_id] as f64)
+                                    .ceil() as u32,
+                            );
+                        }
+                    }
+                }
+                challenge_data.num_qualifiers = num_qualifiers;
+                challenge_data.average_solution_ratio = if num_qualifiers == 0 {
+                    0.0
+                } else {
+                    sum_weighted_solution_ratio / num_qualifiers as f64
+                };
                 break;
             }
-            let difficulty_parameters = &config.challenges.difficulty_parameters[challenge_id];
-            let min_difficulty = difficulty_parameters.min_difficulty();
-            let max_difficulty = difficulty_parameters.max_difficulty();
-            if (0..difficulty.len())
-                .into_iter()
-                .any(|i| difficulty[i] < min_difficulty[i] || difficulty[i] > max_difficulty[i])
-            {
-                continue;
-            }
-            curr_frontier_index = frontier_indexes[difficulty];
-            let player_data = active_opow_block_data.get_mut(player_id).unwrap();
-            let algorithm_data = active_algorithms_block_data.get_mut(algorithm_id).unwrap();
-
-            let max_qualifiers = max_qualifiers_by_player.get(player_id).unwrap().clone();
-            let solution_ratio = num_solutions as f64 / num_nonces as f64;
-            let num_qualifiers = if solution_ratio >= min_solution_ratio {
-                num_solutions.min(max_qualifiers)
-            } else {
-                0
-            };
-            max_qualifiers_by_player.insert(player_id.clone(), max_qualifiers - num_qualifiers);
-
-            if num_qualifiers > 0 {
-                *player_data
-                    .num_qualifiers_by_challenge
-                    .entry(challenge_id.clone())
-                    .or_default() += num_qualifiers;
-                *algorithm_data
-                    .num_qualifiers_by_player
-                    .entry(player_id.clone())
-                    .or_default() += num_qualifiers;
-                challenge_data.num_qualifiers += num_qualifiers;
-            }
-            challenge_data
-                .qualifier_difficulties
-                .insert(difficulty.clone());
         }
     }
 
-    // update reliability
-    for challenge_id in active_challenge_ids.iter() {
-        if !solutions_by_challenge.contains_key(challenge_id) {
-            continue;
-        }
-        let solutions = solutions_by_challenge.get(challenge_id).unwrap();
-        let challenge_data = active_challenges_block_data.get_mut(challenge_id).unwrap();
-
-        let mut total_solutions = HashMap::<String, u32>::new();
-        let mut total_nonces = HashMap::<String, u32>::new();
-        for (settings, num_solutions, num_nonces) in solutions.iter() {
-            if !challenge_data
-                .qualifier_difficulties
-                .contains(&settings.difficulty)
-            {
-                continue;
-            }
-            *total_solutions
-                .entry(settings.player_id.clone())
-                .or_default() += *num_solutions;
-            *total_nonces.entry(settings.player_id.clone()).or_default() += *num_nonces;
-        }
-
-        let mut sum_weighted_solution_ratio = 0.0;
-        for player_id in total_solutions.keys() {
-            let solution_ratio = total_solutions[player_id] as f64 / total_nonces[player_id] as f64;
-            let opow_data = active_opow_block_data.get_mut(player_id).unwrap();
-            if let Some(&num_qualifiers) = opow_data.num_qualifiers_by_challenge.get(challenge_id) {
-                sum_weighted_solution_ratio += solution_ratio * num_qualifiers as f64;
-            }
-            opow_data
-                .solution_ratio_by_challenge
-                .insert(challenge_id.clone(), solution_ratio);
-        }
-        challenge_data.average_solution_ratio =
-            sum_weighted_solution_ratio / challenge_data.num_qualifiers as f64;
-    }
-
     // update frontiers
     for challenge_id in active_challenge_ids.iter() {
         let challenge_data = active_challenges_block_data.get_mut(challenge_id).unwrap();
diff --git a/tig-structs/src/config.rs b/tig-structs/src/config.rs
index 58e67a3d..3bc9314f 100644
--- a/tig-structs/src/config.rs
+++ b/tig-structs/src/config.rs
@@ -68,7 +68,6 @@ serializable_struct_with_getters! {
         min_per_nonce_fee: PreciseNumber,
         min_base_fee: PreciseNumber,
         runtime_configs: HashMap<AlgorithmType, RuntimeConfig>,
-        min_nonces: HashMap<String, u32>,
     }
 }
 serializable_struct_with_getters! {
@@ -114,6 +113,7 @@ serializable_struct_with_getters! {
         max_coinbase_outputs: usize,
         coinbase_update_period: u32,
         min_solution_ratio_factor: f64,
+        min_num_nonces: u32,
     }
 }
 serializable_struct_with_getters! {