Thanks!!
10 gallons is a good size for a goldfish! Great job there.
However, this size can actually work against you in situations like this. With the lack of filter for a day, it isn’t necessarily the quality of the water. The only exception here is if you are over-feeding. Excess waste (both food and poop) will create water quality issues and pretty quickly.
I suspect the lack of filter (which as a byproduct produces oxygen into the water) and not having air bubbles, your goldfish is quite stressed during this time. Gasping leads me to be concerned moreso with air quality than water quality.
Increasing oxygen levels will allow the goldfish to relax. When you change water, this would be a good time to supplement air. Also, make sure you have plants that naturally oxygenate the water.
I would recommend:
Might I recommend one of these bad boys to prevent accidental mouth / fish water encounters in the future?
It works well for me. I blast the trigger like five or six times and water starts flowing seamlessly. Also I feel like an underwater space alien officer pulling that pump trigger
You mean something like this?
hygger Aquarium Gravel Cleaner, New Quick Water Changer with Air-Pressing Button Fish Tank Sand Cleaner Kit Aquarium Siphon Vacuum Cleaner with Water Hose Controller Clamp https://www.amazon.com/dp/B083NRD2HJ/ref=cm_sw_r_apan_glt_fabc_SFBYRN8VFBWJW8N3FM5H
When I first got my tank, I struggled with tank cleanings. But then I got a hand held siphon gun and it makes things so much easier! I would recommend it. Here’s a link to one.
You get a aquarium gravel vac like this but you can get less fancy ones
There is also more narrow siphons you can get online like this hyger one.
I personally went to lowes and got some PVC fittings and necked down my siphon to a 3/4" opening for narrow spaces in the tank instead of moving my hardscape around.
Ooh your setup sounds amazing!! The waterfall I’m using is actually a filter (it’s a Tetra Decorative Reptofilter) but I expect the water to still get pretty gross so I bought an inexpensive mini water vacuum on Amazon so I can suction out the water every week. https://www.amazon.com/Aquarium-Cleaner-Changer-Air-Pressing-Controller/dp/B083NRD2HJ
I give blood worms as a treat once per week, on the day before I do a water change. I use one of these to vacuum the bottom on changes: https://www.amazon.com/dp/B083NRD2HJ?psc=1&ref=ppx_yo2_dt_b_product_details