Freshwater tanks

Question
QUESTION: I have been keeping a freshwater tanks for almost all my life. Although I have a problem where whenever I put new water into the tank after I clean it or just adding water, it seems to turn a yellowish tint in like 2-3 days. Is it just the light reflecting off of the rocks, or is it something else?

ANSWER: Hi Thomas,

A few things cause a yellowish tint in the water. Tannic acids will stain water amber colored, this can be happening if you have a lot of bogwood or driftwood in your tank. Also if you are using peat in the filter or substrate.

Another thing that can make the water yellowish is just your water - does it have a yellow tint? Some well water does. You should look at a glass of water right out of the tap. Does it have sediment in it that falls to the bottom? Does it smell or have any color to it? Minerals can cause this.

Test your straight tap water with a freshwater test kit. The pH is not usually important - as long as it is somewhere higher than 6.0 and lower than 8.0, it's fine. pH outside of those ranges will require that you choose community fish more carefully, and instead look for fish that thrive in these extremes. Take special note of your alkalinity - extremely low alkalinity is problematic because it means your aquarium water is prone to dramatic shifts in water chemistry. Alkalinity in an aquarium is what "buffers" the pH and keeps the water chemistry stable. If you have very low alkalinity, you may need to buffer it...let's cross that bridge when we get there. Test your water first with a test kit. I find the strips very convenient and inexpensive. I got a pack of 50 5-in-1 test strips, Jungle brand, for a little over $10. I definitely recommend you have a test kit.

If the yellow tint in the water is tannic acid, it can probably be absorbed with carbon without trouble. Just add some fresh activated carbon to your filter somehow, either a fresh cartridge (if your filter is that type) or add some activated carbon in a bag to your canister filter. Or you can do the same with an additional hang-on back filter. A stocking or pantyhose works just as well as a media bag.

If the yellowish tint is because of something odd or off about your water chemistry, you need to be aware of it. Get your water tested, and write back if you would like more clarification or advice. A link to an excellent article on water chemistry in the freshwater aquarium, is below:
http://www.wetwebmedia.com/FWSubWebIndex/fwh2oquality.htm

I really doubt that your rocks are causing your water to change color in a few days. I would be really curious to know your tank size, your filtration, and the inhabitants of your tank. Or plural, if you have multiple tanks.

Feel free to write again. Take care and happy holidays!
Nicole

---------- FOLLOW-UP ----------

QUESTION: Thanks Nicole as for the tanks size, I have a 29 gallon tank, I do have some driftwood for the plecos because I know they love it and my filtration is a Whisper 4.0 Power Filter with the Whisper Disposable Cartrages.

Answer
Hi Thomas,

Do you have more than one common pleco in your tank? Common plecos get to be huge, over 1 foot long. I would not keep one in anything less than a 75 gallon tank as an adult. If you have two dwarf plecos (like bristlenose or clown plecos) this is fine, but if you have two common plecos, rehome one and eventually both - they will REALLY pollute your tank.

Hopefully you are moderately stocked. 29 gallon tanks are not as big as they seem, they are best suited to several small fishes and a couple of medium sized fish. OR lots of little fish. OR a couple of fancy goldfish, and that's it.

It would help if your filtration could be improved or supplemented. I recommend a canister filter. There are some very economical ones that Penn Plax makes, I have one I bought for $50 and it helped take the strain off my AquaClear hang-on back filter. If you do get another filter, leave the old one running. It always helps to have "redundant filtration" (more than one filter running) - in case one fails, and so that both sides of the tank have filtration and the water circulates evenly.

And you're right, plecos need to nibble wood to be healthy. It helps their digestion, and keeps them happy.

I hope that helps! Have a nice weekend.
Nicole