Leopard moray help

[clxtchsxns]

Hey so recently I came into possession of a Leopard Moray eel she is about 30 cm long and is living in a 35 gallon for now (I only just got her and will update her tank soon) she seems to be doing fine I fed her yesterday and she enjoyed it but today I lifted her lid and it smelt a little off I tested my water level and they all seemed to be alright it was just my phosphate was a little bit high so I moved a refugium with macro algae, some cycled sand, a 2 month old sponge filter and a little bit of live rock. The lid is nothing special its just some pvc board with a 5L water jug weighing the lids down. After I finished testing the water parameters I put it down to some of the leftover food and her pooping a lot while the bacteria eats the ammonia some of the ammonia floated to the top and turned into gas and sorta sat there under the lid, I took off the lid for about 10 minutes and it didn't stink anymore. I decided to cut some little strips out on the sides and middle of each piece but I don't think that'll be enough. I'm currently running a HOB Tidal55 and a refugium with macro algae, a 2 month old sponge filter and some sand and rock.
I also noticed she is breathing a little fast opening her jaw to breath every second, I plan on turning on old 10 gal into a sump for it soon I just need time.

 

[KrisReef]

Quit feed that eel until you get a large enough biofilter or change water often, but everything that fish eats is going to come out and need to be handled by the biofilter, water changes, or both. The can last a long time between meals, but they will die quick in dirty water.

 

[clxtchsxns]

Quit feed that eel until you get a large enough biofilter or change water often, but everything that fish eats is going to come out and need to be handled by the biofilter, water changes, or both. The can last a long time between meals, but they will die quick in dirty water.

I had a zebra moray in there before and no problems but ill do the sump soon