80 gal. tank

Question
QUESTION: I have an 80 gal. tank with 10 african cichlids its been set up for approx. 6 yrs doing very good. I want to change the gravel in the tank to a new color along with new decorations how do I even begin? I have no clue and I don't want to loose any fishes.

ANSWER: Hi Martha,

I am so sorry not to get back to you sooner, I am just getting ready to go on vacation and have been really busy.

I have a 55 gallon tank with African cichlids which needs redoing from time to time (since they dig huge caves which collapse rock structures every now and then) and this is what I do. Follow these steps and I believe you will not have any trouble with fish dying:

1. Set up a Rubbermaid tub with a heater and filter, much like a quarantine tank. It will probably have to be set up for several hours, perhaps even a full day, so it needs some aeration. In my experience, filtration will be necessary in a tub of 15-20 gallons, but if you have a really big tub, something like 35 gallons, you can get away with just using a powerhead for water circulation or an air pump and bubble wand. Don't feed the fish (they'll be fine going hungry for a little while) and try to put some floating plants on the top, like a big plastic plant. This will discourage any jumping. You may not need a heater if your house stays 72 degrees or warmer.

2. Put the fish in the tub. The tub should be filled with water from the main tank, so it shouldn't shock them. Catching the fish may involve dismantling the tank...it does for me, African cichlids are the best hiders!

3. Drain the tank. Make sure you shut the heater off, since it can crack if it isn't submerged. You don't really need to keep any of the old water, just make sure to follow the next step which is critical.

4. KEEP THE FILTER MEDIA BIOLOGICALLY ACTIVE. This is very important! Most people think that the beneficial bacteria is in their filter, their water, their gravel, their decorations...and really, almost all of it is in their filter. Unless you were using an undergravel filter, the gravel was probably not that biologically active anyhow, and the decorations probably had some algae and some beneficial bacteria, but this is really nothing compared to the amount of beneficial bacteria contained in the filter media. Thus, it is crucial that you get a bucket (or a tub) full of water, and let the filter run in that, while you do the rearranging and the gravel swap. Water passing through the filter media will make sure it stays alive. What I do, is I use the filter to keep the water circulating in the tub the fish are in!

5. Remove the decorations. It is best that if you are using any of the old decorations, that you keep them wet, so as to keep any beneficial bacteria that may be on them...unless you need to clean them, in that case just use hot water and a toothbrush. You will be killing any beneficial bacteria on them, but as I say, it isn't much anyhow.

6. Remove the gravel. I find that an empty yogurt container (the big containers, not those little ones) will work really well because you can squeeze it to get just the right shape you need. There will always be a little gravel left over that you just can't get at. Just push it towards the back of the tank - you won't even notice it.

7. Rinse the new gravel in a bucket (or buckets) until the water comes out clear instead of cloudy, then add it to the tank. Sloping it towards the back so that it's lower in the front is the traditional way to do it. The water circulation pattern that this creates encourage the debris to be sucked up by the filters. Also, it makes your tank look bigger.

After this, you are ready for the decorations. Take your time with this, it's easiest to do when there isn't water in the tank - even though it makes the plastic plants wilt. Now you are ready to fill up the tank. (I presume with such a big tank that you have some kind of hose arrangement and you are not using buckets!) Don't forget to add dechlorinator and return the heater to the tank if you took it out.

Put the filter or filters back on the new tank. Let everything settle, it will probably look sort of cloudy at first, but in about an hour it should be much clearer. When it looks almost as clear as usual, you're ready to return the fish, which will be hungry and cranky by now!

I hope that helps, take care.
Nicole

P.S. You might also like to check out this article:
http://freshaquarium.about.com/cs/qa/l/blqa2008.htm

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

QUESTION: Thank you so much Nicole for all your instructions which are very easy to understand and follow, just one more question do I return any water from the holding tank into the new tank? or do I just return the fish after it looks clear? Again, thank you and have a great vacation!

Answer
Hi again Martha,

Thank you! It's my pleasure to help.

This really is up to you. I can tell you that I have returned my cichlids to a tank full of 100% new water and they have been fine with it, they actually seem really excited! Cichlids love clean water, and provided the new water is close in temperature to the old water, and is treated with dechlorinator, it ought to be just fine.

However, some people feel like an 100% water change is a shock to the fish, and like to reintroduce some of the old water. If you kept 20% of the water from your old tank (16 gallons) you could leave a few inches unfilled, and then put the old water on top of the new water.

If you ask me, it doesn't make much difference either way to African cichlids. There are definitely some fussy fish, such as the frail gourami, which gets its name for a reason!...and of course, there are fussy cichlids, like wild caught discus. Based on personal experience and reading, I feel certain that African cichlids would do just fine in a tank of all new water (as long as the filter bacteria did not get harmed), so that's my opinion. Of course, it wouldn't hurt for you to return some of the old water if you felt more comfortable doing that!

I hope that helps. Enjoy your newly aquascaped aquarium! I only wish I had such a big tank for my brood, which are going to spend the summer in a 650 gallon pond...if I can only get around to catching them. ;)

Take care,
Nicole