Yes, if you are not trolling I apologize.
Unfortunately, you have either been given bad information from some source, or have not researched the keeping of seahorses.
However that can all be rectified.
First I would recommend removing the chromis as long term they are most likely to stress the seahorses to the point the seahorses may stop eating and perish.
Second, just to be sure about the cycle, I would be testing at least daily for ammonia and be prepared to remove the seahorses if ammonia appears.
The research could be started by reading the links at the
bottom of "
My Thoughts on Seahorse Keeping" that have been written by experienced seahorse keepers and an important piece by Dan Underwood of seahorsesource.com
The tankmates guide can give you insight into what may work for you, but it's not recommended to have tankmates until you've successfully kept the seahorses for a good period of time.
Also, with three seahorses in there now, by the guidlines, you are maxed for stock load.
As mentioned, seahorses make for very dirty tanks due to the fact that they are very selective on the pieces of food they eat, and, the fact that they masticate the food as they snick it up and pass food particulate matter through the gills into the water.
This nutrient bioload, while possibly feeding algae, will also feed nasty bacteria like vibriosis which may get out of control and negatively affect the sensitive seahorses. Keeping the temperature in a range of 68° to 74° is a means to help control this possibility, but some keepers succeed at higher temperatures, probably with higher due diligence to housekeeping.