There is no point getting disillusioned with the water changes. The more water changes, the better of course, but really, a compromise to 2X-3X per week will be OK. Change 99% instead of 50%. It doesn't take that much longer. When you drop the water level and expose the leaves to air, wipe the leaves with your index finger and thumb so that the slime rubs off. When the feeling is more a rough surface instead of being slick then you will have removed one more barrier to gas movement across the leaf/water interface. Try to do the change just before the lights on if possible, but if not possible then don't worry about it, but clean the leaves. So, do fewer changes, but maximize the effectiveness of the water change by immaculately cleaning the tank.
If you are short of cash, then wait a bit before buying the Koralia. I think you mentioned that you saw the problem plants start to improve. So just save your money, wait and see if they continue to improve and only buy the pump if the improvement stops and if deterioration starts.
Again, the fundamental problems has been gas exchange in the plants. Adjusting the injection rate even higher will be an effective strategy for now when combined with your spraybar configuration. A little bit of elbow grease is called for now to keep things improving. Light exacerbates the problems of poor gas exchange and that is why the diatoms appear.
You need to change you perception of algae. This is so very important. They are not foreign invaders into the tank. They are part of the eco-system in every way, exactly as are the bacteria you are trying to propagate. Algal blooms are a sign of weak plants in exactly the same way as rotting leaves or translucent tissue are. So the worst thing you can do is to attack the problem by trying to hide the symptoms. That's another reason I think surface skimmers and so forth are such an illusion. You WANT to see the symptoms exposed so that you can address it properly, instead of creating an optical illusion that there is no problem. If you hide the problem instead of fixing it then the problem will later manifest itself in some more terrible way. Then you will be scratching your head trying to understand why you had that next terrible problem. Diatoms are the first indicator of poor gas exchange combined with too much light. They just happent to be quicker off the mark than some other species. When the problem chronic and then becomes more acute those other species will then take advantage.
Algae are predators. They are not competitors. Predators wait patiently to find and attack the weak. Therefore, do everything to maximize plant health and the predators will see that there is no point wasting energy chasing healthy prey.
Cheers,
If you are short of cash, then wait a bit before buying the Koralia. I think you mentioned that you saw the problem plants start to improve. So just save your money, wait and see if they continue to improve and only buy the pump if the improvement stops and if deterioration starts.
Again, the fundamental problems has been gas exchange in the plants. Adjusting the injection rate even higher will be an effective strategy for now when combined with your spraybar configuration. A little bit of elbow grease is called for now to keep things improving. Light exacerbates the problems of poor gas exchange and that is why the diatoms appear.
You need to change you perception of algae. This is so very important. They are not foreign invaders into the tank. They are part of the eco-system in every way, exactly as are the bacteria you are trying to propagate. Algal blooms are a sign of weak plants in exactly the same way as rotting leaves or translucent tissue are. So the worst thing you can do is to attack the problem by trying to hide the symptoms. That's another reason I think surface skimmers and so forth are such an illusion. You WANT to see the symptoms exposed so that you can address it properly, instead of creating an optical illusion that there is no problem. If you hide the problem instead of fixing it then the problem will later manifest itself in some more terrible way. Then you will be scratching your head trying to understand why you had that next terrible problem. Diatoms are the first indicator of poor gas exchange combined with too much light. They just happent to be quicker off the mark than some other species. When the problem chronic and then becomes more acute those other species will then take advantage.
Algae are predators. They are not competitors. Predators wait patiently to find and attack the weak. Therefore, do everything to maximize plant health and the predators will see that there is no point wasting energy chasing healthy prey.
Cheers,