How Do Ya'll Do Large % W/c

[zoogy]

Okay, I've had just enuf spirits to let me ask the silly newbie questions.... I am an abosulte novice, so I hope you'll allow me some leeway to ask a few obvious questions. I read ya'll talking about doing big % water changes. 60%, 70%, even (OMG ) 90% water changes. My big question is... how is that even physically possible?

I admit that I fell into the lfs sales trap of believing that 10% weekly w/c during the cycle (fish-in cycling... didn't know any better before hand ) would be more than adequate and 20% w/c every 2 months after that would suffice. I have since given that idea up as a pipe dream and quite a good sales pitch. I now understand that much more frequent and extensive w/c are required. But I honestly don't understand how to physically do that? If I empty 90% of my water my filter will just be sucking air (and that just doesn't seem right), and my plants... well I can't even imagine it.

I only have a 5 gallon bucket (that's 18.9 liters for my dear friends in the UK) to w/c a 30 gallon tank. And even if I could find a bigger bucket, I wouldn't be able to lift it. Is four 15% water changes effectively the same as a 60% change, or do I lose too much in dimishing returns? (Come on - I know there are some math gods on this forum) Do I shut off my filter, and if so how long before I risk it drying out? Do I move my fish - they may only have an inch to swim in? What will happen to my plants? Heater on or off?

Please.. someone tell me step by painstaking step how to accomplish a large % w/c.

 

[Katty]

Well say you have like, iunno, 2ppm ammonia or nitrate or fruit juice in in the tank or whatever. Any size tank.
1. take out 15% of water, ppm is still 2 since both water and solute were removed in the same proportions
2. refill tank, ppm is now 1.7 since the new water diluted it by 15%
3. Remove 15% and refill again, ppm is at 1.445
4. Remove 15% and refill, ppm is 1.228
5. Remove 15% and refill, ppm is 1.04
etc. etc. etc. That could take forever... Half water change is a little better since you halve the ppm each time. A 90% would remove 90% of 2 right off the bat, leaving you with .2 ppm after one water change. Not that I'd do a 90% water change either since my fish need room to swim...

Hopefully I did that right... I took chemistry last year so I might be a little rusty. Please correct me if I'm wrong.

 

[drobbyb]

I use a Python type system. Basically it's a valve that attaches to my sink and a long hose with a gravel vacuum attached to the end. You can simply turn on your water and put the gravel vacuum end into your tank, and it will suck all the water out. This is a little wasteful on the water, so what I do is take the valve off, start the siphon manually, and lay the now free end across my floor and out the door to the garden. This uses gravity to drain the tank, and having it go into the garden, none of the water is wasted. To refill your tank, put the valve end back on and attach it to the sink. You simply turn the bottom of the assembly, and tap water flows straight into the tank. You have to dose the full volume of the tank when you change water this way, but it sure beats carrying buckets!

 

[notg2009]

Okay, I've had just enuf spirits to let me ask the silly newbie questions.... I am an abosulte novice, so I hope you'll allow me some leeway to ask a few obvious questions. I read ya'll talking about doing big % water changes. 60%, 70%, even (OMG ) 90% water changes. My big question is... how is that even physically possible?

I admit that I fell into the lfs sales trap of believing that 10% weekly w/c during the cycle (fish-in cycling... didn't know any better before hand ) would be more than adequate and 20% w/c every 2 months after that would suffice. I have since given that idea up as a pipe dream and quite a good sales pitch. I now understand that much more frequent and extensive w/c are required. But I honestly don't understand how to physically do that? If I empty 90% of my water my filter will just be sucking air (and that just doesn't seem right), and my plants... well I can't even imagine it.

I only have a 5 gallon bucket (that's 18.9 liters for my dear friends in the UK) to w/c a 30 gallon tank. And even if I could find a bigger bucket, I wouldn't be able to lift it. Is four 15% water changes effectively the same as a 60% change, or do I lose too much in dimishing returns? (Come on - I know there are some math gods on this forum) Do I shut off my filter, and if so how long before I risk it drying out? Do I move my fish - they may only have an inch to swim in? What will happen to my plants? Heater on or off?

Please.. someone tell me step by painstaking step how to accomplish a large % w/c.

Hey there, first off let me tell you that people on this site are quite helpful and nice!! I've got a lot of great advice so far

As for the water changes, I think over 60% water changes are only in times of crisis!! usually you don't need that huge of a w/c if you are dealing with reasonable amounts of ammonia, nitrite, nitrate, etc. Also instead of doing an 80% water change per week, you can do 10%-20% every other day. That should take care of toxic nitrogen-containing compounds.
I don't use a bucket to remove the water. I got a tube with a plastic bulb (pump) in the middle of it and some extra tubing. It stretches all the way to the toilet and you can vacuum the bottom of the tank to get the wastes out. You pump until water starts flowing. Use the bucket to get fresh water, use a conditioner that takes care of chlorine, chloramine, ammonia, etc. I hope this helps.

Well say you have like, iunno, 2ppm ammonia or nitrate or fruit juice in in the tank or whatever. Any size tank.
1. take out 15% of water, ppm is still 2 since both water and solute were removed in the same proportions
2. refill tank, ppm is now 1.7 since the new water diluted it by 15%
3. Remove 15% and refill again, ppm is at 1.445
4. Remove 15% and refill, ppm is 1.228
5. Remove 15% and refill, ppm is 1.04
etc. etc. etc. That could take forever... Half water change is a little better since you halve the ppm each time. A 90% would remove 90% of 2 right off the bat, leaving you with .2 ppm after one water change. Not that I'd do a 90% water change either since my fish need room to swim...

Hopefully I did that right... I took chemistry last year so I might be a little rusty. Please correct me if I'm wrong.

That is some fine math but it depends on the ammonia in the tap water as well. Assuming that you neutralize ammonia that is released from chloramine breakdown then your numbers are rightttttt


please correct me if I'm wrong

 

[symon_say]

It depends on the facilities you have, for me for example, my yard is about 5 ft from my tank and i can put a siphon and drain my tank in just a few minutes, to fill the tank i just put a hose, and some dechlorinator and i'm done. That was a large 90% W/C after the fishless cycle.

For small water changes and to measure the change i use a 5 gallon bucket, i siphon the water to then, and to fill i have a small submersible pump that i put in the buckets with clean water.

And yes, shut down your filter and heater. Try get a hose that can go outside or to some place were you can throw the tank water, that way you won't have to carry the bucket, and in your case that you have fish in the tank you'll have to do the water change in smaller % to keep the water levels right and don't change the parameters that much.

 

[waterdrop]

You shut your filter and heater off in necessary (I use an external filter and heater, so they can both keep running during even pretty large water changes, but most normal HOBs and internals need to be shut off and internal tube heaters definately need to be turned off. The media will stay wet and that is fine for a long long time.

Many of us use hose systems rather than buckets. I use a thing called a Python, just because they make a large array of faucet adapters and have good hoses and other options. The aquarium end has a large clear gravel cleaning cylinder that attaches to a hose that can be bought in various lengths. Mine stretches out the door, then down a hall like 30 feet, then into the bathroom and into a catchbucket (so I'll have leftover tank water to do stuff with) where the water overflows into the tub drain (in the summer the catchbucket is outdoors.)

After the old water is gravel-cleaned and siphoned out to the catch-bucket, I grab a large plastic cup full and set it on the sink. I then plunge my hand in the cup and alternately under the stream of water from the faucet and adjust the temperature until they match. I then leave the faucet lever in this temperature position but turn the water off and attach the Python hose to the faucet via a brass adapter. I then return up the hall to the aquarium (at this point I dose the tank with a 1.5x dose of Prime for the full volume of the tank) and make sure the cylinder end is in the tank pointing at something that won't be hurt by the inflow and I partially close the tank lid to further keep the hose from moving around. I then go back to the faucet and turn it on full force with it still set to the perfect tank temperature. I then go back and watch it fill the tank (30G would take about 4 minutes, the entire maintenance session takes about 30 min.) I make a point to watch the water coming in and do not allow myself to get distracted so I won't ever have an overflow accident. I turn off the faucet when the water line just hits the bottom of the upper tank rim, which is about an inch wide and allows me some working room even when the water line is no longer visible from the front glass.

After the fill I re-dose the plant fertilizers (if this is a running tank, or I re-dose the ammonia if this is a fishless cycling tank) and turn back on any equipment that was turned off (a circulation powerhead in my case.) I coil the Python back up and put it under the sink and put away the other stuff. (If this was a filter cleaning weekend I would have cleaned the filter in the catchbucket water before refilling the tank.)

The two most important things a beginner should do when performing water changes (especially when they are larger than about 25%) are to properly "condition" the water and to "roughly temperature match." A conditioner product's most important function is to neutralize chlorine and chloramine additives and it's ideal to dose it at about 1.5x what the manufacturer says and not more than 2x if you still have a young tank (under a year.) Rough temperature matching can be done with your hand but you should compare several times, to be more sure. There is no need to match with a thermometer. As far as fish and plants go, they can take a lower level than you think but you do sometimes have to make a judgement call about that, especially in the case of large difficult-to-support plants.

Hope this helps a little,

~~waterdrop~~

 

[Essjay]

If you still want to use your bucket to take the water out, say you want to remove 10 galls with your 5 gall bucket, when the bucket is getting nearly full, put your thumb over the bucket end of the tube and put it under the water in the tank. Then empty the bucket, thumb over the bucket end of the tube again and put it back in the bucket. Then fill the bucket again. So long as you keep your thumb over the bucket end of the tube, or keep it under water in the tank while you are emptying the first bucket of water you won't have to start the siphon again, it'll just carry on when you put the tube back in the bucket.

This is what I do. I can't carry a heavy bucket (bad back) so I do three small bucket fulls on my 30ish gall tank, and 1.5 bucket fulls on my 15ish gall tank. (sorry, know the volumes in litres, not galls, so rough conversion)

 

[Aqua Tom]

I have a 10 meter length of food grade clear hose that I syphon straight into the drain, using it to clean my sand at the same time.

To refill Uriel gave me a great tip. I jury rig the hose to my electric shower output, set the temp to near as i can tank temp & fill it up. The wife isnt to happy with having hoses all over the house but she likes the fish so is biting her lip.

 

[Curiosity101]

Also just to add another tip. If you need to do a massive water change. Or if it's got so bad that you'll need to do say... two 80% changes?

You don't need to fill the entire tank up to take it all out again.

Imagine you've remove 20gals of water.

Replace with 10gals. You've now got 50% of the original concentration of stuff.

You can now start removing water again. 10 gal out and then fully refil.

If you do the maths you end up having done an 83% water change... (Someone correct me if I'm wrong)

You don't have to completely refil after the first 10gal replace and removal btw. Just do the smaller changes on the smaller volume of water until you've done enough. Then fully refil.

 

[karin]

A python is worth the investment. Love it every time I use it.

 

[Gilli]

No need to buy an expensive Python. Ive got a cheap self start gravel cleaner (the type you shake up and down to start) - just bought myself a length of hose cheap off Ebay to attach to it long enough to reach my loo(my tank is in the living room). The suction is strong enough to gravel vac at the same as emptying the tank even though the hose is 8 meters long!

 

[zoogy]

Thanks to everyone for the great advice! I undertook a 60% w/c this morning, following your advice and I think I've just about got my toxins under control. Really love the suggestion to re-purpose the old tank water to use in the garden, I will definately be doing that this summer. Waterdrop, thanks for taking the time to write in such detail it really helped.

Don't have any fancy equipment yet so I had to do it with a short syphon hose and the trusty 5 gallon bucket. Lots of trips to the sink and 2 mouthfuls of fish water. But my fish finally look completely healthy again so it was worth it in the end.

 

[waterdrop]

Great! Glad these discussions have been helping, this is really a great forum with lots of members pitching in.

I sometimes think the added knowledge surrounding water changing skills and filter maintenance skills has really meant more to me in my own fishkeeping than cycling skills have, even though we probably talk about the cycling topic more here.

The actual doing of water changes and of proper filter cleans really makes a huge difference for the average hobbyist and there are plenty of little tips that keep coming to be added to these skills.

~~waterdrop~~

 

[Rynofasho]

As an aside, and since it sounds like you're cycling with fish, if you just changed two buckets a day you'd be MORE than good.

And don't forget to turn the heater back on! I've done that a few times and found some frosty fish!

 

[MikeO]

Zoogy - How far is your tank from a door (assuming its ground floor?).

I, as many do, just have a big tube which I manully syphon out into the garden, then use a bucket to refill - I am 260L and usually do 80-90% once a month and refilling with a bucket doesnt really take that long to do.

Remember to turn your heater off 20mins or so BEFORE you drain because if it is on, or off but still hot, it will crack out of the water, then if you dont notice, refill and turn on......well need i say more.

I always turn my filters off too. In fact I turn everything off.

If you want a good place to buy a nice thick tube let me know....I buy tubing from a brilliant website that has every type of tube known to man and its pretty cheap.