[fish_4_all]

I do a 50%+ water change each week. Sometimes my fish don't mind, other times they pout for a day or so.

Here are some key factors when you do a water change:

Know your GH and to a less extent, your KH. Large swings in either one can cause stress to the fish until they acclimate again. When I do my water changes, I immediately do my macro dosing to try and keep the GH and KH swings as short as possible and as little as possible. I also add my dechlorinator immediately after the water change. If you want to, you can add the dechlor, MgSO4 and your Calcium to the water if you are using buckets.

Another key is temperature. My fish almost revolt against me when the temperature is higher than the water in the tank. I always shoot for about 2 dergees below tank temperature for my water changes.

One other thing is you are changing a little too much if you are doing 75% of the water. Unless you balance your KH and GH, the swings in both can be very stressful.

You may also be seeing a large swing in your pH. Test your tank and test your tap water after you leave the tap water out for 24 hours. This will allow the CO2 to gas out and give you a more accurate reading. If the swing in pH is too large and your KH is below 3 dKH, (~48ppm I think) then your fish will stress and it can be very harmful to them.

Do you inject CO2 for plants?
Is the test kit you are using a liquid regent or test strips?

A lot of things can cause stress at a water change but we need to know what your KH, GH, pH of tank and tap water and anything you dose as far as ferts, what type of dechlorinator and anything else you add to really help you properly.

 

[fish_4_all]

Well it could be a couple things then. Room temp is often colder than your tanks, 5-10 degrees is really gonna stress fish out, espcially tetras and especially with a 75% water change. It could be hard water but it shouldn't matter as far as your GH and KH unless your well water is fluctuating a lot, which is unlikely but possible.

If you want to stay with the same thing you are doing right now, simply change less water. 40-50% will be plenty assuming you have a normal bioload. This should help the fish stress and getting the temp closer to what is in the tank will help too.

IMHO, you should always use some kind of dechlorinator simply because it not only removes chlorine and chloramine but also removes heavy metals which could also be a problem especially if your well water is anything like what I was brought up. Never needed to take a mineral suppliment for sure.

HTH

 

[fish_4_all]

First, my neons do the same thing. When the lights come on they look like ghosts but color up during the day.

As for water changes, I don't think once a month is enough, not by far. Yes, the plants use up a lot of stuff, yes they do make a tank more balanced but there are things that plants don't remove. These are salts, undissolved solids from both fish waste and decaying plant matter. And anything in the water as far as undissolved and dissolved matter that builds up over time. Also, ever time you add water to the tank to compensate for evaporation, you put more heavy metals into the tank and other dfissolved an undissolved soilds that will build up over time.

Gravel vacs are extremely important unless you have complete coverage of your substrate and simply can not gravel vac. I have a massive plant load in my 10 gallon tanks and I make sure to gravel vac as much as possible because huge amounts of gunk collect in the substrate if you don't. Worst case scenario, the builup of Gunk creates an anarobic pocket and hydrogen sulfide builds up to the point it realeses and kills all your fish. I have never had this happen but have heard the first hand stories of a tank going form perfect to smelling like ritten eggs with a tank full of dead fish in the morning. I also do not overfeed and probably underfeed because my fish will almost jump out the tank for food.

I could agree with a heavily planted tank and doing a once a month water change if you only have 10 neons in 55 gallon tank. Any sort of medium to heavy bioload and I would never go longer than 2 weeks nor less than a 50% water change. IMHO