So does changing so much not take out too much bacteria? Its constantly a learning process this.
No. Bacteria live on submerged surfaces in what is termed the biofilm. When you do the water change next time, gently run your fingertips over such a surface, like the side or rear glass (which presumably are not "cleaned" all the time) or a leaf, and you will feel it as slippery or sort of slimy. This is the biofilm. Bacteria colonize this (there are many different species, all good as far as what we are discussing) along with algae and microscopic critters. Usually you cannot see any of this, but it is the reason many fish will graze surfaces, they are looking for food.
Bacteria are very sticky, and it is not easy to dislodge them. The front glass should be cleaned at every water change with one of those sponge scrapers. This prevents the biofilm from getting too thick, which usually results in algae that can be harder to remove once it is settled.
Bacteria will colonize every particle of the substrate, and the filter media. More bacteria live in the substrate than in tyhe filter, which is why the substrate is more important. It also hosts more types of bacteria, again all good, whether aerobic or anaerobic.
Also byron do mid dwelling fish come to the top for food or do they stay in the middle. All the danios act like they've never been fed but the glowlights just stay lower down. Do you think they'll work out to go to the top or do they need a different type of food?
Most fish that swim at a level in the upper water column will feed from the surface but remain down at "their" level otherwise. Some fish swim all over the tank. Some fish may tend to remain at their level and wait for the food to fall down. Substrate fish generally never come to the surface to feed as they expect their food to be in the substrate.
Fish should always appear "hungry." It is their inherent instinct to eat when food is available. In an aquarium this can easily result in gross overfeeding. Good quality flake food, and small pellet foods like Bug Bites, will generally be readily eaten by upper fish (as opposed to substrate fish). The substrate fish must have sinking foods; never rely on the flake food getting down to them. Unless you are overfeeding, the upper fish will consume all of this long before it can get to the substrate. The pellet foods like Bug Bites is a bit different. Corydoras and loaches may graze on sinking tablets/pellets/disks for an hour or longer.
I think I'm over feeding through worry not all fish are eating. I was feeding every other day but I'm starting to think of feeding everyday but small amounts just once a day instead of probably too much every other day
Fish should not be fed more often than once each day, except for fry which need more frequent feedings. Missing a day, or two days, or even three days each week will do no harm. I feed the dry prepared foods daily for three days, then a fast day, then a feed day, then the water change day when they get their "treat" of frozen daphnia and bloodworms a couple hours after the water change (nothing before, ever), then the second fast day because the W/C feeding is substantial.
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