diff --git a/core/api/src/servers/exporter.ts b/core/api/src/servers/exporter.ts
index 36936dba14..9b67d7a179 100644
--- a/core/api/src/servers/exporter.ts
+++ b/core/api/src/servers/exporter.ts
@@ -211,7 +211,10 @@ const main = async () => {
   activateLndHealthCheck()
 }
 
-setupMongoConnection()
+setupMongoConnection({
+  syncIndexes: false,
+  options: { readPreference: "secondaryPreferred" },
+})
   .then(() => main())
   .catch((err) => logger.error(err))
 
diff --git a/core/api/src/services/ledger/index.ts b/core/api/src/services/ledger/index.ts
index 9c14c8f409..e6f71b316e 100644
--- a/core/api/src/services/ledger/index.ts
+++ b/core/api/src/services/ledger/index.ts
@@ -312,12 +312,9 @@ export const LedgerService = (): ILedgerService => {
   ): Promise<Satoshis | LedgerError> => {
     const liabilitiesWalletId = toLiabilitiesWalletId(walletId)
     try {
-      const { balance } = await MainBook.balance(
-        {
-          account: liabilitiesWalletId,
-        },
-        { readPreference: "primaryPreferred" },
-      )
+      const { balance } = await MainBook.balance({
+        account: liabilitiesWalletId,
+      })
       if (balance < 0) {
         const dealerUsdWalletId = await caching.getDealerUsdWalletId()
         const dealerBtcWalletId = await caching.getDealerBtcWalletId()
@@ -343,12 +340,9 @@ export const LedgerService = (): ILedgerService => {
   ): Promise<BalanceAmount<S> | LedgerError> => {
     const liabilitiesWalletId = toLiabilitiesWalletId(walletDescriptor.id)
     try {
-      const { balance } = await MainBook.balance(
-        {
-          account: liabilitiesWalletId,
-        },
-        { readPreference: "primaryPreferred" },
-      )
+      const { balance } = await MainBook.balance({
+        account: liabilitiesWalletId,
+      })
       if (balance < 0) {
         const dealerWalletIds = Object.values(await caching.getDealerWalletIds())