Some cyno removers contain erythromycin.
I have seen way to many crashes with chemiclean.. I have asked what is in it and they wont tell me, I am guessing it is oxydator like maybe permanganate since they say no erythromycin. Is there any purple specs in in it? permanganate also can turn the water purple/pink.
Sorry about the crash.
This is a general statement to all who have cyano problems:
Cyno is extremely abundant and eventually be reintroduced to your aquarium and next time it will be far worse if the problem is not taken care of.
You need to find the limiting factor and cut it off and that is phosphates. That cyano is using up phosphates and if you kill it with a chemical those phosphates will continue to grow and cause even bigger problems like bind to your rock or substrate and once that happens your in for a real treat trying to rid your tank of phosphates.. That is really the main reason people have so many issues with algae. Right now that cyano bacteria is actually doing you a favor and warning you of a problem and using up that phosphates.
Find the source of the phosphates.. It in most cases is improper nutrient export or too much nutrient import. Nutrient import can be from over feeding or overcrowding.. It also could be coming in through make up water or water used for water changes if the water is not properly treated with a ro/di system.. Nutrient export could be done through a properly sized skimmer or water changes. Some people us other things like Phosphate removers which can help get things back under control too..
It could be too late and the cyano could be pulling bound phosphates from the rock or substrate. Substrate can be changed if that is the problem.. If it is coming from the rock it can take a while.... Start siphoning out the slime algae, by doing this you are removing the nutrients directly.
Cyno is one of the easier too control algae, really a bacteria and is a good learning point on how to keep algae under control.. Bubble algae, dictyota, dinoflagellates, bryopsis are far harder.
Almost everyone has some cyno in their tank, it is just kept under control and most of the time you dont see it.
My real problem with using chemical to rid yourself of a problem is you dont learn anything and when a bigger problem creeps up you end up with a crash.