I was on vacation for some time and my tank built up a high nitrate level. (no ammonia or nitrite though, yay). I of course did a big water change but it is still fairly high. Which will be more stressful to my fish: another big water change, or highish nitrate until the next regular change? The first big change was on the 10th.
Also, i have a lot of rocks and plants (fake) and i know it's important to vacuum the gravel frequently but is it necessary to move all my plants and rocks every time or is it ok just vacuum the open areas? Also, how often should i vacuum the gravel? I've heard all kinds of things from every single time to almost never.
Nitrate is only a problem for fish are really high concentrations (don't know the exact amount). You can do daily 30 to even 50% water changes without stressing the fish too much. Changing say 40% twice a week may be more appropriate until the levels of nitrate are lower.
I vacuum the open areas, going around the ornaments for most cleanings but, as needed, I move them to get the stuff that accumulates at their bases. I vacuum the gravel once a week when I do a 30-50% water change (varies by tank). It's tanks with live plants that people sometimes say not to vacuum as it could disturb the plants. If there's a lot of waste though, I think it's better to get that out.
What works best for me is,,,When cleaning my 30 or my 55 gal tanks i do a 1/4 water change once a week. I also remove all plants and ornaments from 1/2 of the tank and am usally able to vacume 1/2 of the rocks. Then the next week i do the other side the same way.