Water Changes

[hfjacinto]

Hello all,

What are the recommended water changes for aquariums, I have 3 tanks and I change them as follows:

Note all tanks are: PH 7.2 to 7.4, no nitrite or ammnonia. Total hardness is in the 160 MG. I don't measure for nitrate (should I?)

Tank 1) 10 gallon tank lightly stocked with cory's and platy's, I do 50% a week (25% , 2 times a week)

Tank 2) 30 gallon barrel (outdoors) with 4 large fantail goldfish and heavily planted in warmer months. I do 20% a week (10%, 2 times a week). Also since the tank is heated it never freezes during winter, but should I stop water changes since the fish aren't eating?

Tank 3) 45 gallon tall (show tank), fully stocked with dense plantings, Rainbows, cory's, 3 fancy pleco's and a 6 inch Gibby. I do 40% a week (20% 2 times a week).

The water is aged tap water, I don't use any chlorine remover as I age the water for 1-2 weeks before I use it. There is no chlorine or chloramin after 1 week of aging, there is a lot of chlorine at the tap. Should I do larger water changes (50% to 60% a week) on the show tank?

[Barbie]

Testing nitrate levels will show you exactly how stable your water parameters are. Fish waste is converted by bacteria from ammonia to nitrite to nitrate. That nitrate has nowhere to go unless you have a planted aquarium, or do frequent partial water changes. That's actually why it tends to be the indicator for stocking and maintenance levels. If it's building up, you either need to reduce the fish load and feeding levels, or change water more often, basically.

When you say you pretreat the water for a week, do you do that just for offgassing the chlorine? That should be accomplished in about 24 hours, usually.

I change 30-40% of my tank volume water on most of the tanks in my house at least once a week. This keeps all of them, even the overstocked grow out tanks, below 40ppm nitrates. For sensitive stock, their tanks aren't as full of fish, so the levels don't climb as rapidly.

As to changing the water on the outside tank, I can't help with that one. Sorry. I know that pond type conditions and how to winter fish are an area I just don't have experience in. Hopefully we'll find someone else here that will ;).

Barbie

[hfjacinto]

Barbie,

Thanks for the reply, I store the water in gallon jugs in the garage and after daily testing, I still had measurable chlorine in the aged tap water after 4 days. To be safe I just don't use any gallons of water that are not at least 7 days old.

I used to use a dechlorinater and conditioner but I discovered that most dechlorimators also remove heavy metals. As I was iron dosing with each water change, the declorinator was locking up the iron and the plants weren't growing. Now I just use aged tap water.

[Owch]

Use a heavy metal and chlorine filter, then add your iron.

Problem solved.

Good for drinking water too.

I use a HMA filter from a UK discus supplier. They are branded with the shop logo, but the units are actually from an American company called Pentek Filtration

HMA will not alter the pH or hardness, but will remove chlorine, heavy metals and bacterial cycsts and the like. You can even get a special cartridge to remove chloramines for a few extra £'s.

Cost £130 for a 3 stage unit comprising 1 micron particle filter, 1 micron chlorine/chloramine filter (ChlorPlus 10) and 0.5 micron heavy metal filter (CBR2-10). Replacement cartridges were only £30 for a full set.

Running cost was very low, especially when compared to chemical chlorine/heavy metal removal. Initially it was £0.43 for 100 litres, this dropped to £0.16 when the cartriges were replaced.

As I keep discus, I do lots of water changes, so Ive plumbed a water line from the HMA directly into my tank, connected to a float cut off switch. Flow is set to 0.5litres/min (the HMA is more effective at lower flow rates, also the drop in tank temperature isn't as dramatic) I just siphon 50 liters a day from the tank and leave it to fill up without having to worry about overflowing the tank (which has happened all too often )

I hope this helps

Tom

[Barbie]

Ahhh, yes, small surface area and no surface disturbance would greatly slow down the process. I definitely recommend a dechlorinating agent. You'd save yourself a huge amount of time. I run water directly from my tap into my tanks to refill, adding drops as I go. I have 1300 gallons of water going most of the time and there are fish in some of the tanks that are quite literally not replaceable. I promise, it works great without stressing the fish.

Barbie