I would go for getting four more tiger barbs, definitely. They tend to swim in groups of 5-7 even when kept amongs a whole bunch of other tiger barbs . . . and they become "awkward fin nippers" if they don't have a small amoung of each other to bother. (I have 6 that tend to do just that and ignore the other fish.) However, if you were to get more, you may overstock your tank, so that may sway this idea into not getting more tiger barbs. As for the algae eater, I wouldn't get a pleco that either grows to be large or is large; that will outgrow your tank and quickly at that. Perhaps a Rubber-Lipped Pleco would do the trick, although even they grow to 5". I don't know if otocinclus (sp) cats remove algae, but if they do, they are ideal; they only grow to about 1.5" each. Hope this helps and good luck!
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