Stcnks

Hello! Here's the answers to the Q&A:
1) ammonia 0ppm, nitrite 0 PPM, nitrate 40ppm, pH 7.8, temperature 78°F
2) set up 5 months, last month 2 guppies had Camanallus, 1 treatment for internal parasites with Jungle Anti-Parasite Medicated Fish Food (this weekend is time for treatment 2), used Parasite Clear Tank Buddies 4 weeks ago
3) 2 dwarf gourami, 1 powder blue dwarf gourami, 1 cardinal dwarf gouramin, 3 male guppies, 9 neons, 2 otos
4. change filter every 4 weeks, water change 25% once a week. I add aquarium salts and Jungle start right to new water added.
5) omega one super color flakes daily, omega one freeze dried brine shrimp couple times a week, green marine algae once a week, aquarian algae eater every other day, peas every other week, zucchini slice every other week
6) 33 gallon, marineland 150 hang on filter, rocks, 2 plants, driftwood
7) I am aware of the aquarium nitrogen cycle, I started with a few guppies

Here's my questions/problem:
I purchased a guppy, powder blue and cardinal gourami on August 13. I didn't quarantine them. Shortly after one dwarf gourami started having part of it's side fins disappear and and almost completely lost its pectoral "feeler" fins. I treated for parasites for a guppy and the gourami's fins cleared up without additional treatment.
The side fins grew back fine, the "feeler" fins started growing and grew back bent in the middle at 90° but it seemed fine. I was thinking the fin damage was caused more from the stress of his new tankmates.
A couple weeks ago the gourami started acting like it was working harder than the others to swim and it would rest at the bottom after activity. He doesn't "hang" effortlessly in the water like the other gourami. It is eating normally, guarding it's territory, responding and looking good. It just lays down in the rocks most of the time now when not defending, eating or reacting to my presence. I'm not sure if I should be concerned or not.
I am due to start a second treatment with the medicated parasite food this weekend.
Should I be doing more for my dwarf?

Thanks!

Amanda

What do you mean by changing your filter? Are you completely changing your media? This really shouldn't be done too often, as it can put your tank into a mini cycle. Also, your nitrates are a bit high.
Other than that, I would dose again this weekend for parasites, as it sounds like your dwarf is still being effected. But I would put him in a QT, since it is not advisable to medicate the main tank.

Stcnks

The Marineland has a biowheel and a replaceable carbon filter cartridge. I replace the carbon filter cartridge every 4 weeks. The biowheel remains the same.