How Much Water Movement is too Much?

I have two young axolotls; I have a filtration system suggested for a 5 gallon tank ( I have a 30 gallon ) and an air pump with air stone to supply oxygen on the other side of the tank. I just plugged the air pump back in today because when I plugged it in the first time, the axolotls seemed uncomfortable. They don't seem to mind it this time around. I'm just wondering if I have too much water movement . I've heard that too much can lead to axies having issues and losing their gills. I want them to have enough oxygen and a clean tank, as well as keeping their gills and being comfortable. Overall health is the key goal here. I intentionally installed the smaller filtration system for the low amount of water movement it produces, but I do water changes weekly and clean ups daily. I'm just looking for suggestions, ideas, and criticism. My tank is a 30 gallon; 2.5 ft long; 1 ft wide; 1.5 ft tall. If I have too much water movement please let me know! :happy: Here are some visuals:

Your axolotls look fine, and as long as your water parameters are good it shouldn't be a problem having a smaller filter.
I over filter my tanks (50 gal tank, 2 x 50 gal filters) and keep the water movement to a minimum by having the spray bar under the surface, and pointing upwards and towards the tank wall.
There are several threads on the fourm about reducing water flow, so you could have a look at those. Reducing water movement usually involves putting something in the way, such as plants, decor, putting a tall hide under the output of the filter, or attaching some clean filter media/sponge/etc. to your filter outflow.
I hope this helps. :happy:

I don't think axolotls mind air stones/bubblers to be honest, but if your h.o.b. filter is producing too much flow that it is replacing the sand, you could consider adding an ornament to block it. Or you can attach a sponge on the end of it! (although that can create an oily surface, because you have an air stone, an oil slick won't collect on the surface of the water.)

Also, I know you are trying to keep the water flow low, but a 5gal filter might be too small for a 30gal tank. If your parameters keep up though, I would think it's nothing to worry about!!

I over filter my tanks to make sure the water stays clean, as well as weekly 25% changes and daily clean ups. I have a 20gal long with a filter for a 50gal. To reduce the water flow, I have a floating turtle dock with a sponge on top, right under the output. I also turned the flow down a tiny bit. I have an air stone near the top as well, to keep the water from getting a film with the reduced current. When you look at the plants in the tank, the only ones moving are the floating on es, so there's no current to bother him.

You will know if they are bothered because their gills will curl and their tails will too.