diff --git a/freqtrade/util/coin_gecko.py b/freqtrade/util/coin_gecko.py
index c39721c00..47b80875b 100644
--- a/freqtrade/util/coin_gecko.py
+++ b/freqtrade/util/coin_gecko.py
@@ -16,10 +16,11 @@ class FtCoinGeckoApi(CoinGeckoAPI):
         # Doint' pass api_key to parent, instead set the header on the session directly
         self._api_key = api_key
 
-        if api_key and is_demo:
-            # Use demo api key
-            self.api_base_url = self.__API_URL_BASE
-            self.session.params.update({"x_cg_demo_api_key": api_key})
-        else:
+        if api_key and not is_demo:
             self.api_base_url = self.__PRO_API_URL_BASE
             self.session.params.update({"x_cg_pro_api_key": api_key})
+        else:
+            # Use demo api key
+            self.api_base_url = self.__API_URL_BASE
+            if api_key:
+                self.session.params.update({"x_cg_demo_api_key": api_key})
diff --git a/tests/rpc/test_fiat_convert.py b/tests/rpc/test_fiat_convert.py
index 4d502b32b..75b6fd0b4 100644
--- a/tests/rpc/test_fiat_convert.py
+++ b/tests/rpc/test_fiat_convert.py
@@ -8,6 +8,7 @@ import pytest
 from requests.exceptions import RequestException
 
 from freqtrade.rpc.fiat_convert import CryptoToFiatConverter
+from freqtrade.util.coin_gecko import FtCoinGeckoApi
 from tests.conftest import log_has, log_has_re
 
 
@@ -201,3 +202,18 @@ def test_convert_amount(mocker):
         crypto_amount="1.23", crypto_symbol="BTC", fiat_symbol="BTC"
     )
     assert result == 1.23
+
+
+def test_FtCoinGeckoApi():
+    ftc = FtCoinGeckoApi()
+    assert ftc._api_key == ""
+    assert ftc.api_base_url == "https://api.coingecko.com/api/v3/"
+
+    # defaults to demo
+    ftc = FtCoinGeckoApi(api_key="123456")
+    assert ftc._api_key == "123456"
+    assert ftc.api_base_url == "https://api.coingecko.com/api/v3/"
+
+    ftc = FtCoinGeckoApi(api_key="123456", is_demo=False)
+    assert ftc._api_key == "123456"
+    assert ftc.api_base_url == "https://pro-api.coingecko.com/api/v3/"