I have over 20 Bubble Tip Anemones in my tank. I have learned quite a bit about them over the past few years but continue to learn something new every time I turn around. Basically the two water parameters I concern myself with in reference to the BTAs is Nitrates and Phosphates. Typically the BTA likes Nitrates around 10 ppm and Phosphates under 0.04 ppm. That is the range where they thrive the best. This does not mean that anything away from these targets will cause a BTA to perish. In fact, they are very tolerable to water conditions when the conditions gradually change. Like all living creatures in your aquarium, they do not tolerate rapid changes very well. The one chemical that can have the greatest detrimental effect on your BTA is Ammonia. They do not normally tolerate any ammonia levels. Otherwise, your basic acceptable water parameters are fine for BTA's. Like fish, they need to be carefully acclimated when being placed into a new aquarium. I drip acclimate mine over a 1 hour period and then float them to temp acclimate them for 30 minutes.
One factor that has the greatest effect on adding a new BTA is lighting. My basic rule is if the BTA comes from here locally and I know what lighting it was under, I will try to place it under the same intensity or a lower intensity. If I had the BTA shipped in then I will always choose to place it under low intensity lighting. Once the BTA is in my tank for a couple days I will gradually increase the lighting intensity back up to where I normally keep the tank. Depending on how low I initially set the intensity, it may take up to three weeks to work it back up to my normal lighting intensity. I run Radion Pro fixtures 17" above my tank at varied intensity during the day with the peak being 100% for two hours at midday, so it is easy for me to set the lights to acclimation mode. Generally, I purchase all of my BTAs from one supplier out of LA, California and I know his lighting parameters, so I know what they have been accustomed to. Do not believe the old wives tale that a BTA will always move to where it feels comfortable with the lighting. That is not a guaranteed rule. Also lighting has the biggest effect on the coloration of the BTA. There have been many incidents where a hobbyist purchased a BTA and after placing it in his tank at home, it looked nothing like it had looked in the store. In fact, my supplier uses T-5 lights and a BTA I receive from him will look different in my tank. We regularly exchange photos of the BTAs. A basic rule of thumb is that a BTA will do well under 150 to 250 PAR if acclimated to the lighting.
Another factor influencing the BTA will be flow. They do not normally like direct flow. Usually a BTA will do best in an environment where the flow causes the tentacles to dance around lazily. They will not do well in an area of no flow. They need water movement to wash away anything they expel. It's a pleasure to watch a BTA host a clownfish but it is not absolutely necessary to the BTA.
Let's talk about feeding.... Oh yes, there is plenty of controversy on this subject. Do I feed? What do I feed? How often do I feed? There is no set rule for this. A Bubble Tip Anemone will receive most, if not all of the energy it needs from light. In a properly lighted aquarium the BTA will do well without additional feeding. If you wish for your BTA to grow quickly and produce clones then you should provide additional feeding every 3 to 5 days. There are a number of suitable foods that can be fed. Basically feed a meaty food such as clams, shrimp, or scallops. Contrary to popular opinion, I feed mine Silversides. There are many who will tell you not to feed Silverside but I have had success so I just don't feel like changing. With that said, I am considering testing out Krill instead if I can find a good supply of frozen krill. The amount to feed at a time is something you just kind of have to experiment with. I start all new BTAs that are 3" or larger with about a 1/4" square of food. I uses frozen Mysis for any BTA smaller than 3". If they don't like it or it is simply too much for them, they will spit it back out undigested. I gradually increase the amount over a period of months. I have had BTAs that would eat 2 whole Silversides about 2" long twice a week. They would devour the Silversides and they double in size about every 6 to 8 weeks. Every time they split they would split into at least three clones. So this is just something you have to experiment with and no two BTAs are going to react identically.
C A U T I O N ! ! ! Nothing I have written is a hard and fast rule. These are creatures of nature and each will react somewhat differently under different circumstances. A basic rule is keep your water parameters where you normally would for most Marine Fish (exception is a bit higher Nitrates than normally advised is good for BTAs) and provide them with sufficient lighting. Everything else is somewhat experimental, just take it slow and use common sense.
There are plenty of written articles that can be found on the Internet about BTA Care. Read what you can and try to take bits and pieces away from each article. I found it essential not to rely on one article no matter who wrote it. And never let someone tell you why a BTA might bubble up at the tips and why it may quit doing so. Not even the most renown scientist have figured it out yet. Everything you hear about this phenomenon is strictly opinion. My personal opinion is this phenomenon has to do with the overall size of the BTA and the intensity of lighting it is under. My experience is that larger BTAs are less likely to bubble up and many BTAs will bubble up under very intense lighting but will lose their bubble tips when the lighting intensity is reduced or when the BTA gets larger (6"+)
Hope this gives you some food for thought...
That is when it started to go downhill for whatever reason.
It sounds like you caught it in time though so your tank didn't suffer as well.
