Is it better to do a larger or smaller water change on a 2 1/2 gallon fish tank?

Question

My 2 1/2 gallon tank that has a tiny pleco and some commen guppies in it has high nitrate. I know larger tanks, but on a smaller tank is it better to do a larger water change or a few smaller ones. The filter I have on it is one for a ten gallon tank.

Answer 1

It's great that you have such good filtration on that tank! With high nitrates I would do a 30 - 50% water change (but do be careful with the water temperature) and check it again tomorrow, doing another big change if need be til those nitrates are lower.

I hate to say it, but you'll probably continue to have worse and worse water quality problems until you rehome that pleco. If it's a common pleco (which is the one most often sold in petstores) then it has a max adult size of 18" to 2 feet and is an ammonia factory even for a fish that size.

Answer 2

You can try 20 - 30 % water changes every 2-3 days to try to lower the Nitrate levels (recommended for whatever size tank you have). If that doesn't work try doing a 50 % for the same time period. Just remember to use a conditioner to remove the chlorine,ammonia and metals from tap water.
I usually fill 2 - 10 gallon buckets with fresh water right after changing to let it sit for a few days for eliminating some of chlorine and to bring it to a more tolerable temp.

Remember .... Not many Plecos stay "tiny" for long.

Answer 3

it's all about proportions, do the typical 25% or so, or on that tank just over 1/2 gallon each time. The nitrates are probably high from the over stocking... that is if you have more than a few guppies. You don;t want to do huge water changes if you can help it, that changes all kinds of water chemistry and can be harmful to the fish. Try increasing the frequency of the water changes to every two days or even daily to remedy the problem, then just do them like a normal tank. If they creep back up, start doing the changes every 4 days or so. Small tanks are a lot of fun, but sometimes can be a bit of extra work.

Best of luck with your micro tank, they are cool!

Answer 4

First you should place about a gallon jug of water preferably in a glass container somewhere and let it sit for 2 to 3 days. Then change only 10% of the water each week. As your water runs low in the jug you have been letting sit, refill it. Just make sure that you do the refill on your gallon jug right after doing a change in your fish tank. That way it has time to sit before the next change.

Answer 5

it doesn't matter weather its a small tank or a big tank. if u want to change some of the water then u should change no more than 10% of the water. cause ur just goin to mess with the biology of the water if u change too much. plus this will stress the fish out if u change to much. 10% every week. never do a complete water change.

Answer 6

if you want to keep plecos and guppies i suggest large water changes. it will be virtually impossible to cycle it with a pleco and guppies. unless you have like 2 guppies and the pleco is the size of your fingernail. im not quite sure you could get high nitrate -- that is usually in well established tanks or overplanted tanks.

Answer 7

Nitrate can be dealt with by performing a 20 - 30% water change each week.

Answer 8

Take out a gallon and you should be fine and change filters 2 to3 days before or after a water change

Answer 9

Your tanks is overstocked. But change as much water as you can. There is nothing beneficial in the water. Keep it around the same temp and use dechlor.

Answer 10

large change the whole tank as long as the nitrate is high. try a bio-wheel filter for the nitrate or use synthetic nitrate reducers.