Glad to hear the Ray is ok
If the tank is mature then I would not add cycle as you shouldnt need it. The cloudy water could also be bacterial bloom from the cycle.
For Sky: Personally I would not use HOB as a main filter for rays as they just seem way too small to get decent filter area for the bacteria to live on, plus they do not seem to be able to handle large amounts of waste.
Good quality water changes (check the tap water parameters too - including Nitrite) cover up a lot of filter weaknesses but I personally would try to pick up some external cannisters (even if 2nd hand) and clean them out of sync...i.e. 1 every other month say which means that each filter is mature at different times and only wash out using tank water
If the tank is mature then I would not add cycle as you shouldnt need it. The cloudy water could also be bacterial bloom from the cycle.
For Sky: Personally I would not use HOB as a main filter for rays as they just seem way too small to get decent filter area for the bacteria to live on, plus they do not seem to be able to handle large amounts of waste.
Good quality water changes (check the tap water parameters too - including Nitrite) cover up a lot of filter weaknesses but I personally would try to pick up some external cannisters (even if 2nd hand) and clean them out of sync...i.e. 1 every other month say which means that each filter is mature at different times and only wash out using tank water